Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    if t > 3:
        return 'No'
    return 'Yes'

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']

    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    if t > 3:
        return 'No'
    return 'Yes'

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')

    if len(lst) != 2:
        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

        return 'No'
    if not lst[1] in suf:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

        return 'No'
    if not lst[1] in suf:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

    if t > 3:
        return 'No'
    return 'Yes'

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:

        return 'No'
    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'

        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'

    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if not lst[1] in suf:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'

        return 'No'
    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'

    if not lst[0][0].isalpha():
        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'

        return 'No'
    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'


Prompt:
def file_name_check(file_name):
    """Create a function which takes a string representing a file's name, and returns
    'Yes' if the the file's name is valid, and returns 'No' otherwise.
    A file's name is considered to be valid if and only if all the following conditions
    are met:
    - There should not be more than three digits ('0'-'9') in the file's name.
    - The file's name contains exactly one dot '.'
    - The substring before the dot should not be empty, and it starts with a letter from
    the latin alphapet ('a'-'z' and 'A'-'Z').
    - The substring after the dot should be one of these: ['txt', 'exe', 'dll']
    Examples:
    file_name_check("example.txt") # => 'Yes'
    file_name_check("1example.dll") # => 'No' (the name should start with a latin alphapet letter)
    """
    suf = ['txt', 'exe', 'dll']
    lst = file_name.split(sep='.')
    if len(lst) != 2:
        return 'No'

    t = len([x for x in lst[0] if x.isdigit()])
    if t > 3:
        return 'No'
    return 'Yes'

    if not lst[1] in suf:
        return 'No'
    if len(lst[0]) == 0:
        return 'No'
    if not lst[0][0].isalpha():
        return 'No'

def check(candidate):

    # Check some simple cases
    assert candidate("example.txt") == 'Yes'
    assert candidate("1example.dll") == 'No'
    assert candidate('s1sdf3.asd') == 'No'
    assert candidate('K.dll') == 'Yes'
    assert candidate('MY16FILE3.exe') == 'Yes'
    assert candidate('His12FILE94.exe') == 'No'
    assert candidate('_Y.txt') == 'No'
    assert candidate('?aREYA.exe') == 'No'
    assert candidate('/this_is_valid.dll') == 'No'
    assert candidate('this_is_valid.wow') == 'No'
    assert candidate('this_is_valid.txt') == 'Yes'
    assert candidate('this_is_valid.txtexe') == 'No'
    assert candidate('#this2_i4s_5valid.ten') == 'No'
    assert candidate('@this1_is6_valid.exe') == 'No'
    assert candidate('this_is_12valid.6exe4.txt') == 'No'
    assert candidate('all.exe.txt') == 'No'
    assert candidate('I563_No.exe') == 'Yes'
    assert candidate('Is3youfault.txt') == 'Yes'
    assert candidate('no_one#knows.dll') == 'Yes'
    assert candidate('1I563_Yes3.exe') == 'No'
    assert candidate('I563_Yes3.txtt') == 'No'
    assert candidate('final..txt') == 'No'
    assert candidate('final132') == 'No'
    assert candidate('_f4indsartal132.') == 'No'

    # Check some edge cases that are easy to work out by hand.
    assert candidate('.txt') == 'No'
    assert candidate('s.') == 'No'