Day 20 Of 100DaysofCode: Writing a OOP code To Read Text File And Find Number Of Word
Tags: 100daysofcode, codenewbie, beginners, python
Published: 2021-01-13 15:12:21

Today I had learned more about regular expression. I tried to write some code in regular expression. I took help from python access to web data from [Coursera](https://www.coursera.org/learn/python-network-data/lecture/5LN6R/11-2-extracting-data). Also I took the help of goggle also.

I tried to write one code in class. Which handle the text file.

# File Handler Class
In object-oriented programming, a class is an extensible program-code-template for creating objects, providing initial values for state. My code about file handle in class is given below. At first I initialize the class by giving file directory.after that I tried to write line read the file and place each line in the list. After that I initialize empty list as attribute of class to store each number and each words.
Initialize empty dictionary as attribute of class to store each occurance of number and words.
```python
class FileHandler:
    def __init__(self,filename = None):
        self.file = open(filename)
        self.lines = [line.strip() for line in self.file.readlines()]
        self.numbers = []
        self.words = []
        self.num_occur = {}
        self.word_occur = {} 
   ```
I tried to make a method to find all the words in file and place it in list declared earlier.

```python
    def get_words(self):
        total = []
        for line in self.lines:
            
            line = line.rstrip()
            words = re.findall('(?!\d)\w+',line)
            #print(type(words))
            if len(words) == 0 :continue
            total.extend(words)
        self.words = total
        return total
   ```
After that I made a method to find all the numbers in file and place it in list declared earlier.

   ```python
    def get_numbers(self):
        total = []
        
        for line in self.lines:
            line = line.rstrip()
            words = re.findall('[0-9]+',line)
            if len(words) == 0:continue
            num = [int(i) for i in words]
            total.extend(num)
        self.numbers = total
        return total
    ```

  Method to find occurance of each word in file. For this I used 
 len of total word.

   ```python
    def get_occur_words(self):
        total = []
        count = 0
        for line in self.lines:
            line = line.rstrip()
            words = re.findall('(?!\d)\w+',line)
            if len(words) == 0:continue
            
            total.extend(words)
        self.occur_words = len(total)
        return len(total)
  ```
  Method to find occurance of each number in a file

```python
    def get_occur_numbers(self):
        total = []
        count = 0
        for line in self.lines:
            line = line.rstrip()
            words = re.findall('[0-9]+',line)
            if len(words) == 0:continue
            num = [int(i) for i in words]
            total.extend(num)
        self.occur_numbers = len(total)
        return len(total)
fileH = FileHandler('file2.txt')
print(fileH.get_words())
print(fileH.get_numbers())
print(fileH.get_occur_words())
print(fileH.get_occur_numbers())

```
Finally my code look like

```python
class FileHandler:
    def __init__(self,filename = None):
        self.file = open(filename)
        self.lines = [line.strip() for line in self.file.readlines()]
        self.numbers = []
        self.words = []
        self.num_occur = {}
        self.word_occur = {}
    def get_words(self):
        total = []
        for line in self.lines:
            
            line = line.rstrip()
            words = re.findall('(?!\d)\w+',line)
            #print(type(words))
            if len(words) == 0 :continue
            total.extend(words)
        self.words = total
        return total
    def get_numbers(self):
        total = []
        
        for line in self.lines:
            line = line.rstrip()
            words = re.findall('[0-9]+',line)
            if len(words) == 0:continue
            num = [int(i) for i in words]
            total.extend(num)
        self.numbers = total
        return total
    def get_occur_words(self):
        total = []
        count = 0
        for line in self.lines:
            line = line.rstrip()
            words = re.findall('(?!\d)\w+',line)
            if len(words) == 0:continue
            
            total.extend(words)
        self.occur_words = len(total)
        return len(total)
    def get_occur_numbers(self):
        total = []
        count = 0
        for line in self.lines:
            line = line.rstrip()
            words = re.findall('[0-9]+',line)
            if len(words) == 0:continue
            num = [int(i) for i in words]
            total.extend(num)
        self.occur_numbers = len(total)
        return len(total)
fileH = FileHandler('file2.txt')
print(fileH.get_words())
print(fileH.get_numbers())
print(fileH.get_occur_words())
print(fileH.get_occur_numbers())

```
After runnig this code output is

```python
['This', 'file', 'contains', 'the', 'actual', 'data', 'for', 'your', 'assignment', 'good', 'luck', 'Why', 'should', 'you', 'learn', 'to', 'write', 'programs', 'Writing', 'programs', 'or', 'programming', 'is', 'a', 'very', 'creative', 'and', 'rewarding', 'activity', 'You', 'can', 'write', 'programs', 'for', 'many', 'reasons', 'ranging', 'from', 'making', 'your', 'living', 'to', 'solving', 'a', 'difficult', 'data', 'analysis', 'problem', 'to', 'having', 'fun', 'to', 'helping', 'someone', 'else', 'solve', 'a', 'problem', 'This', 'book', 'assumes', 'that', 'everyone', 'needs', 'to', 'know', 'how', 'to', 'program', 'and', 'that', 'once', 'you', 'know', 'how', 'to', 'program', 'you', 'will', 'figure', 'out', 'what', 'you', 'want', 'to', 'do', 'with', 'your', 'newfound', 'skills', 'We', 'are', 'surrounded', 'in', 'our', 'daily', 'lives', 'with', 'computers', 'ranging', 'from', 'laptops', 'to', 'cell', 'phones', 'We', 'can', 'think', 'of', 'these', 'computers', 'as', 'our', 'personal', 'assistants', 'who', 'can', 'take', 'care', 'of', 'many', 'things', 'on', 'our', 'behalf', 'The', 'hardware', 'in', 'our', 'current', 'day', 'computers', 'is', 'essentially', 'built', 'to', 'continuously', 'ask', 'us', 'the', 'question', 'What', 'would', 'you', 'like', 'me', 'to', 'do', 'next', 'Programmers', 'add', 'an', 'operating', 'system', 'and', 'a', 'set', 'of', 'applications', 'to', 'the', 'hardware', 'and', 'we', 'end', 'up', 'with', 'a', 'Personal', 'Digital', 'Assistant', 'that', 'is', 'quite', 'helpful', 'and', 'capable', 'of', 'helping', 'us', 'do', 'many', 'different', 'things', 'Our', 'computers', 'are', 'fast', 'and', 'have', 'vast', 'amounts', 'of', 'memory', 'and', 'could', 'be', 'very', 'helpful', 'to', 'us', 'if', 'we', 'only', 'knew', 'the', 'language', 'to', 'speak', 'to', 'explain', 'to', 'the', 'computer', 'what', 'we', 'would', 'like', 'it', 'to', 'do', 'next', 'If', 'we', 'knew', 'this', 'language', 'we', 'could', 'tell', 'the', 'computer', 'to', 'do', 'tasks', 'on', 'our', 'behalf', 'that', 'were', 'repetitive', 'Interestingly', 'the', 'kinds', 'of', 'things', 'computers', 'can', 'do', 'best', 'are', 'often', 'the', 'kinds', 'of', 'things', 'that', 'we', 'humans', 'find', 'boring', 'and', 'mind', 'numbing', 'For', 'example', 'look', 'at', 'the', 'first', 'three', 'paragraphs', 'of', 'this', 'chapter', 'and', 'tell', 'me', 'the', 'most', 'commonly', 'used', 'word', 'and', 'how', 'many', 'times', 'the', 'word', 'is', 'used', 'While', 'you', 'were', 'able', 'to', 'read', 'and', 'understand', 'the', 'words', 'in', 'a', 'few', 'seconds', 'counting', 'them', 'is', 'almost', 'painful', 'because', 'it', 'is', 'not', 'the', 'kind', 'of', 'problem', 'that', 'human', 'minds', 'are', 'designed', 'to', 'solve', 'For', 'a', 'computer', 'the', 'opposite', 'is', 'true', 'reading', 'and', 'understanding', 'text', 'from', 'a', 'piece', 'of', 'paper', 'is', 'hard', 'for', 'a', 'computer', 'to', 'do', 'but', 'counting', 'the', 'words', 'and', 'telling', 'you', 'how', 'many', 'times', 'the', 'most', 'used', 'word', 'was', 'used', 'is', 'very', 'easy', 'for', 'the', 'computer', 'Our', 'personal', 'information', 'analysis', 'assistant', 'quickly', 'told', 'us', 'that', 'the', 'word', 'to', 'was', 'used', 'sixteen', 'times', 'in', 'the', 'first', 'three', 'paragraphs', 'of', 'this', 'chapter', 'This', 'very', 'fact', 'that', 'computers', 'are', 'good', 'at', 'things', 'that', 'humans', 'are', 'not', 'is', 'why', 'you', 'need', 'to', 'become', 'skilled', 'at', 'talking', 'computer', 'language', 'Once', 'you', 'learn', 'this', 'new', 'language', 'you', 'can', 'delegate', 'mundane', 'tasks', 'to', 'your', 'partner', 'the', 'computer', 'leaving', 'more', 'time', 'for', 'you', 'to', 'do', 'the', 'things', 'that', 'you', 'are', 'uniquely', 'suited', 'for', 'You', 'bring', 'creativity', 'intuition', 'and', 'inventiveness', 'to', 'this', 'partnership', 'Creativity', 'and', 'motivation', 'While', 'this', 'book', 'is', 'not', 'intended', 'for', 'professional', 'programmers', 'professional', 'programming', 'can', 'be', 'a', 'very', 'rewarding', 'job', 'both', 'financially', 'and', 'personally', 'Building', 'useful', 'elegant', 'and', 'clever', 'programs', 'for', 'others', 'to', 'use', 'is', 'a', 'very', 'creative', 'activity', 'Your', 'computer', 'or', 'Personal', 'Digital', 'Assistant', 'PDA', 'usually', 'contains', 'many', 'different', 'programs', 'from', 'many', 'different', 'groups', 'of', 'programmers', 'each', 'competing', 'for', 'your', 'attention', 'and', 'interest', 'They', 'try', 'their', 'best', 'to', 'meet', 'your', 'needs', 'and', 'give', 'you', 'a', 'great', 'user', 'experience', 'in', 'the', 'process', 'In', 'some', 'situations', 'when', 'you', 'choose', 'a', 'piece', 'of', 'software', 'the', 'programmers', 'are', 'directly', 'compensated', 'because', 'of', 'your', 'choice', 'If', 'we', 'think', 'of', 'programs', 'as', 'the', 'creative', 'output', 'of', 'groups', 'of', 'programmers', 'perhaps', 'the', 'following', 'figure', 'is', 'a', 'more', 'sensible', 'version', 'of', 'our', 'PDA', 'For', 'now', 'our', 'primary', 'motivation', 'is', 'not', 'to', 'make', 'money', 'or', 'please', 'end', 'users', 'but', 'instead', 'for', 'us', 'to', 'be', 'more', 'productive', 'in', 'handling', 'the', 'data', 'and', 'information', 'that', 'we', 'will', 'encounter', 'in', 'our', 'lives', 'When', 'you', 'first', 'start', 'you', 'will', 'be', 'both', 'the', 'programmer', 'and', 'the', 'end', 'user', 'of', 'your', 'programs', 'As', 'you', 'gain', 'skill', 'as', 'a', 'programmer', 'and', 'programming', 'feels', 'more', 'creative', 'to', 'you', 'your', 'thoughts', 'may', 'turn', 'toward', 'developing', 'programs', 'for', 'others', 'Computer', 'hardware', 'architecture', 'Before', 'we', 'start', 'learning', 'the', 'language', 'we', 'speak', 'to', 'give', 'instructions', 'to', 'computers', 'to', 'develop', 'software', 'we', 'need', 'to', 'learn', 'a', 'small', 'amount', 'about', 'how', 'computers', 'are', 'built', 'Central', 'Processing', 'Unit', 'or', 'CPU', 'is', 'the', 'part', 'of', 'the', 'computer', 'that', 'is', 'built', 'to', 'be', 'obsessed', 'with', 'what', 'is', 'next', 'If', 'your', 'computer', 'is', 'rated', 'at', 'three', 'Gigahertz', 'it', 'means', 'that', 'the', 'CPU', 'will', 'ask', 'What', 'next', 'three', 'billion', 'times', 'per', 'second', 'You', 'are', 'going', 'to', 'have', 'to', 'learn', 'how', 'to', 'talk', 'fast', 'to', 'keep', 'up', 'with', 'the', 'CPU', 'Main', 'Memory', 'is', 'used', 'to', 'store', 'information', 'that', 'the', 'CPU', 'needs', 'in', 'a', 'hurry', 'The', 'main', 'memory', 'is', 'nearly', 'as', 'fast', 'as', 'the', 'CPU', 'But', 'the', 'information', 'stored', 'in', 'the', 'main', 'memory', 'vanishes', 'when', 'the', 'computer', 'is', 'turned', 'off', 'Secondary', 'Memory', 'is', 'also', 'used', 'to', 'store', 'information', 'but', 'it', 'is', 'much', 'slower', 'than', 'the', 'main', 'memory', 'The', 'advantage', 'of', 'the', 'secondary', 'memory', 'is', 'that', 'it', 'can', 'store', 'information', 'even', 'when', 'there', 'is', 'no', 'power', 'to', 'the', 'computer', 'Examples', 'of', 'secondary', 'memory', 'are', 'disk', 'drives', 'or', 'flash', 'memory', 'typically', 'found', 'in', 'USB', 'sticks', 'and', 'portable', 'music', 'players', 'Input', 'and', 'Output', 'Devices', 'are', 'simply', 'our', 'screen', 'keyboard', 'mouse', 'microphone', 'speaker', 'touchpad', 'etc', 'They', 'are', 'all', 'of', 'the', 'ways', 'we', 'interact', 'with', 'the', 'computer', 'These', 'days', 'most', 'computers', 'also', 'have', 'a', 'Network', 'Connection', 'to', 'retrieve', 'information', 'over', 'a', 'network', 'We', 'can', 'think', 'of', 'the', 'network', 'as', 'a', 'very', 'slow', 'place', 'to', 'store', 'and', 'retrieve', 'data', 'that', 'might', 'not', 'always', 'be', 'up', 'So', 'in', 'a', 'sense', 'the', 'network', 'is', 'a', 'slower', 'and', 'at', 'times', 'unreliable', 'form', 'of', 'Secondary', 'Memory', 'While', 'most', 'of', 'the', 'detail', 'of', 'how', 'these', 'components', 'work', 'is', 'best', 'left', 'to', 'computer', 'builders', 'it', 'helps', 'to', 'have', 'some', 'terminology', 'so', 'we', 'can', 'talk', 'about', 'these', 'different', 'parts', 'as', 'we', 'write', 'our', 'programs', 'As', 'a', 'programmer', 'your', 'job', 'is', 'to', 'use', 'and', 'orchestrate', 'each', 'of', 'these', 'resources', 'to', 'solve', 'the', 'problem', 'that', 'you', 'need', 'to', 'solve', 'and', 'analyze', 'the', 'data', 'you', 'get', 'from', 'the', 'solution', 'As', 'a', 'programmer', 'you', 'will', 'mostly', 'be', 'talking', 'to', 'the', 'CPU', 'and', 'telling', 'it', 'what', 'to', 'do', 'next', 'Sometimes', 'you', 'will', 'tell', 'the', 'CPU', 'to', 'use', 'the', 'main', 'memory', 'secondary', 'memory', 'network', 'or', 'the', 'input', 'output', 'devices', 'You', 'need', 'to', 'be', 'the', 'person', 'who', 'answers', 'the', 'CPU', 's', 'What', 'next', 'question', 'But', 'it', 'would', 'be', 'very', 'uncomfortable', 'to', 'shrink', 'you', 'down', 'to', 'five', 'mm', 'tall', 'and', 'insert', 'you', 'into', 'the', 'computer', 'just', 'so', 'you', 'could', 'issue', 'a', 'command', 'three', 'billion', 'times', 'per', 'second', 'So', 'instead', 'you', 'must', 'write', 'down', 'your', 'instructions', 'in', 'advance', 'We', 'call', 'these', 'stored', 'instructions', 'a', 'program', 'and', 'the', 'act', 'of', 'writing', 'these', 'instructions', 'down', 'and', 'getting', 'the', 'instructions', 'to', 'be', 'correct', 'programming', 'Understanding', 'programming', 'In', 'the', 'rest', 'of', 'this', 'book', 'we', 'will', 'try', 'to', 'turn', 'you', 'into', 'a', 'person', 'who', 'is', 'skilled', 'in', 'the', 'art', 'of', 'programming', 'In', 'the', 'end', 'you', 'will', 'be', 'a', 'programmer', 'perhaps', 'not', 'a', 'professional', 'programmer', 'but', 'at', 'least', 'you', 'will', 'have', 'the', 'skills', 'to', 'look', 'at', 'a', 'data', 'information', 'analysis', 'problem', 'and', 'develop', 'a', 'program', 'to', 'solve', 'the', 'problem', 'problem', 'solving', 'In', 'a', 'sense', 'you', 'need', 'two', 'skills', 'to', 'be', 'a', 'programmer', 'First', 'you', 'need', 'to', 'know', 'the', 'programming', 'language', 'Python', 'you', 'need', 'to', 'know', 'the', 'vocabulary', 'and', 'the', 'grammar', 'You', 'need', 'to', 'be', 'able', 'to', 'spell', 'the', 'words', 'in', 'this', 'new', 'language', 'properly', 'and', 'know', 'how', 'to', 'construct', 'well', 'formed', 'sentences', 'in', 'this', 'new', 'language', 'Second', 'you', 'need', 'to', 'tell', 'a', 'story', 'In', 'writing', 'a', 'story', 'you', 'combine', 'words', 'and', 'sentences', 'to', 'convey', 'an', 'idea', 'to', 'the', 'reader', 'There', 'is', 'a', 'skill', 'and', 'art', 'in', 'constructing', 'the', 'story', 'and', 'skill', 'in', 'story', 'writing', 'is', 'improved', 'by', 'doing', 'some', 'writing', 'and', 'getting', 'some', 'feedback', 'In', 'programming', 'our', 'program', 'is', 'the', 'story', 'and', 'the', 'problem', 'you', 'are', 'trying', 'to', 'solve', 'is', 'the', 'idea', 'itemize', 'Once', 'you', 'learn', 'one', 'programming', 'language', 'such', 'as', 'Python', 'you', 'will', 'find', 'it', 'much', 'easier', 'to', 'learn', 'a', 'second', 'programming', 'language', 'such', 'as', 'JavaScript', 'or', 'C', 'The', 'new', 'programming', 'language', 'has', 'very', 'different', 'vocabulary', 'and', 'grammar', 'but', 'the', 'problem', 'solving', 'skills', 'will', 'be', 'the', 'same', 'across', 'all', 'programming', 'languages', 'You', 'will', 'learn', 'the', 'vocabulary', 'and', 'sentences', 'of', 'Python', 'pretty', 'quickly', 'It', 'will', 'take', 'longer', 'for', 'you', 'to', 'be', 'able', 'to', 'write', 'a', 'coherent', 'program', 'to', 'solve', 'a', 'brand', 'new', 'problem', 'We', 'teach', 'programming', 'much', 'like', 'we', 'teach', 'writing', 'We', 'start', 'reading', 'and', 'explaining', 'programs', 'then', 'we', 'write', 'simple', 'programs', 'and', 'then', 'we', 'write', 'increasingly', 'complex', 'programs', 'over', 'time', 'At', 'some', 'point', 'you', 'get', 'your', 'muse', 'and', 'see', 'the', 'patterns', 'on', 'your', 'own', 'and', 'can', 'see', 'more', 'naturally', 'how', 'to', 'take', 'a', 'problem', 'and', 'write', 'a', 'program', 'that', 'solves', 'that', 'problem', 'And', 'once', 'you', 'get', 'to', 'that', 'point', 'programming', 'becomes', 'a', 'very', 'pleasant', 'and', 'creative', 'process', 'We', 'start', 'with', 'the', 'vocabulary', 'and', 'structure', 'of', 'Python', 'programs', 'Be', 'patient', 'as', 'the', 'simple', 'examples', 'remind', 'you', 'of', 'when', 'you', 'started', 'reading', 'for', 'the', 'first', 'time', 'Words', 'and', 'sentences', 'Unlike', 'human', 'languages', 'the', 'Python', 'vocabulary', 'is', 'actually', 'pretty', 'small', 'We', 'call', 'this', 'vocabulary', 'the', 'reserved', 'words', 'These', 'are', 'words', 'that', 'have', 'very', 'special', 'meaning', 'to', 'Python', 'When', 'Python', 'sees', 'these', 'words', 'in', 'a', 'Python', 'program', 'they', 'have', 'one', 'and', 'only', 'one', 'meaning', 'to', 'Python', 'Later', 'as', 'you', 'write', 'programs', 'you', 'will', 'make', 'up', 'your', 'own', 'words', 'that', 'have', 'meaning', 'to', 'you', 'called', 'variables', 'You', 'will', 'have', 'great', 'latitude', 'in', 'choosing', 'your', 'names', 'for', 'your', 'variables', 'but', 'you', 'cannot', 'use', 'any', 'of', 'Python', 's', 'reserved', 'words', 'as', 'a', 'name', 'for', 'a', 'variable', 'When', 'we', 'train', 'a', 'dog', 'we', 'use', 'special', 'words', 'like', 'sit', 'stay', 'and', 'fetch', 'When', 'you', 'talk', 'to', 'a', 'dog', 'and', 'don', 't', 'use', 'any', 'of', 'the', 'reserved', 'words', 'they', 'just', 'look', 'at', 'you', 'with', 'a', 'quizzical', 'look', 'on', 'their', 'face', 'until', 'you', 'say', 'a', 'reserved', 'word', 'For', 'example', 'if', 'you', 'say', 'I', 'wish', 'more', 'people', 'would', 'walk', 'to', 'improve', 'their', 'overall', 'health', 'what', 'most', 'dogs', 'likely', 'hear', 'is', 'blah', 'blah', 'blah', 'walk', 'blah', 'blah', 'blah', 'blah', 'That', 'is', 'because', 'walk', 'is', 'a', 'reserved', 'word', 'in', 'dog', 'language', 'The', 'reserved', 'words', 'in', 'the', 'language', 'where', 'humans', 'talk', 'to', 'Python', 'include', 'the', 'following', 'and', 'del', 'from', 'not', 'while', 'as', 'elif', 'global', 'or', 'with', 'assert', 'else', 'if', 'pass', 'yield', 'break', 'except', 'import', 'print', 'class', 'exec', 'in', 'raise', 'continue', 'finally', 'is', 'return', 'def', 'for', 'lambda', 'try', 'That', 'is', 'it', 'and', 'unlike', 'a', 'dog', 'Python', 'is', 'already', 'completely', 'trained', 'When', 'you', 'say', 'try', 'Python', 'will', 'try', 'every', 'time', 'you', 'say', 'it', 'without', 'fail', 'We', 'will', 'learn', 'these', 'reserved', 'words', 'and', 'how', 'they', 'are', 'used', 'in', 'good', 'time', 'but', 'for', 'now', 'we', 'will', 'focus', 'on', 'the', 'Python', 'equivalent', 'of', 'speak', 'in', 'human', 'to', 'dog', 'language', 'The', 'nice', 'thing', 'about', 'telling', 'Python', 'to', 'speak', 'is', 'that', 'we', 'can', 'even', 'tell', 'it', 'what', 'to', 'say', 'by', 'giving', 'it', 'a', 'message', 'in', 'quotes', 'And', 'we', 'have', 'even', 'written', 'our', 'first', 'syntactically', 'correct', 'Python', 'sentence', 'Our', 'sentence', 'starts', 'with', 'the', 'reserved', 'word', 'print', 'followed', 'by', 'a', 'string', 'of', 'text', 'of', 'our', 'choosing', 'enclosed', 'in', 'single', 'quotes', 'Conversing', 'with', 'Python', 'Now', 'that', 'we', 'have', 'a', 'word', 'and', 'a', 'simple', 'sentence', 'that', 'we', 'know', 'in', 'Python', 'we', 'need', 'to', 'know', 'how', 'to', 'start', 'a', 'conversation', 'with', 'Python', 'to', 'test', 'our', 'new', 'language', 'skills', 'Before', 'you', 'can', 'converse', 'with', 'Python', 'you', 'must', 'first', 'install', 'the', 'Python', 'software', 'on', 'your', 'computer', 'and', 'learn', 'how', 'to', 'start', 'Python', 'on', 'your', 'computer', 'That', 'is', 'too', 'much', 'detail', 'for', 'this', 'chapter', 'so', 'I', 'suggest', 'that', 'you', 'consult', 'www', 'py4e', 'com', 'where', 'I', 'have', 'detailed', 'instructions', 'and', 'screencasts', 'of', 'setting', 'up', 'and', 'starting', 'Python', 'on', 'Macintosh', 'and', 'Windows', 'systems', 'At', 'some', 'point', 'you', 'will', 'be', 'in', 'a', 'terminal', 'or', 'command', 'window', 'and', 'you', 'will', 'type', 'python', 'and', 'the', 'Python', 'interpreter', 'will', 'start', 'executing', 'in', 'interactive', 'mode', 'and', 'appear', 'somewhat', 'as', 'follows', 'interactive', 'mode', 'The', 'prompt', 'is', 'the', 'Python', 'interpreter', 's', 'way', 'of', 'asking', 'you', 'What', 'do', 'you', 'want', 'me', 'to', 'do', 'next', 'Python', 'is', 'ready', 'to', 'have', 'a', 'conversation', 'with', 'you', 'All', 'you', 'have', 'to', 'know', 'is', 'how', 'to', 'speak', 'the', 'Python', 'language', 'Let', 's', 'say', 'for', 'example', 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'point', 'right', 'at', 'the', 'line', 'and', 'character', 'where', 'it', 'noticed', 'it', 'was', 'confused', 'The', 'only', 'tricky', 'bit', 'of', 'syntax', 'errors', 'is', 'that', 'sometimes', 'the', 'mistake', 'that', 'needs', 'fixing', 'is', 'actually', 'earlier', 'in', 'the', 'program', 'than', 'where', 'Python', 'noticed', 'it', 'was', 'confused', 'So', 'the', 'line', 'and', 'character', 'that', 'Python', 'indicates', 'in', 'a', 'syntax', 'error', 'may', 'just', 'be', 'a', 'starting', 'point', 'for', 'your', 'investigation', 'A', 'logic', 'error', 'is', 'when', 'your', 'program', 'has', 'good', 'syntax', 'but', 'there', 'is', 'a', 'mistake', 'in', 'the', 'order', 'of', 'the', 'statements', 'or', 'perhaps', 'a', 'mistake', 'in', 'how', 'the', 'statements', 'relate', 'to', 'one', 'another', 'A', 'good', 'example', 'of', 'a', 'logic', 'error', 'might', 'be', 'take', 'a', 'drink', 'from', 'your', 'water', 'bottle', 'put', 'it', 'in', 'your', 'backpack', 'walk', 'to', 'the', 'library', 'and', 'then', 'put', 'the', 'top', 'back', 'on', 'the', 'bottle', 'A', 'semantic', 'error', 'is', 'when', 'your', 'description', 'of', 'the', 'steps', 'to', 'take', 'is', 'syntactically', 'perfect', 'and', 'in', 'the', 'right', 'order', 'but', 'there', 'is', 'simply', 'a', 'mistake', 'in', 'the', 'program', 'The', 'program', 'is', 'perfectly', 'correct', 'but', 'it', 'does', 'not', 'do', 'what', 'you', 'intended', 'for', 'it', 'to', 'do', 'A', 'simple', 'example', 'would', 'be', 'if', 'you', 'were', 'giving', 'a', 'person', 'directions', 'to', 'a', 'restaurant', 'and', 'said', 'when', 'you', 'reach', 'the', 'intersection', 'with', 'the', 'gas', 'station', 'turn', 'left', 'and', 'go', 'one', 'mile', 'and', 'the', 'restaurant', 'is', 'a', 'red', 'building', 'on', 'your', 'left', 'Your', 'friend', 'is', 'very', 'late', 'and', 'calls', 'you', 'to', 'tell', 'you', 'that', 'they', 'are', 'on', 'a', 'farm', 'and', 'walking', 'around', 'behind', 'a', 'barn', 'with', 'no', 'sign', 'of', 'a', 'restaurant', 'Then', 'you', 'say', 'did', 'you', 'turn', 'left', 'or', 'right', 'at', 'the', 'gas', 'station', 'and', 'they', 'say', 'I', 'followed', 'your', 'directions', 'perfectly', 'I', 'have', 'them', 'written', 'down', 'it', 'says', 'turn', 'left', 'and', 'go', 'one', 'mile', 'at', 'the', 'gas', 'station', 'Then', 'you', 'say', 'I', 'am', 'very', 'sorry', 'because', 'while', 'my', 'instructions', 'were', 'syntactically', 'correct', 'they', 'sadly', 'contained', 'a', 'small', 'but', 'undetected', 'semantic', 'error', 'description', 'Again', 'in', 'all', 'three', 'types', 'of', 'errors', 'Python', 'is', 'merely', 'trying', 'its', 'hardest', 'to', 'do', 'exactly', 'what', 'you', 'have', 'asked', 'The', 'learning', 'journey', 'As', 'you', 'progress', 'through', 'the', 'rest', 'of', 'the', 'book', 'don', 't', 'be', 'afraid', 'if', 'the', 'concepts', 'don', 't', 'seem', 'to', 'fit', 'together', 'well', 'the', 'first', 'time', 'When', 'you', 'were', 'learning', 'to', 'speak', 'it', 'was', 'not', 'a', 'problem', 'for', 'your', 'first', 'few', 'years', 'that', 'you', 'just', 'made', 'cute', 'gurgling', 'noises', 'And', 'it', 'was', 'OK', 'if', 'it', 'took', 'six', 'months', 'for', 'you', 'to', 'move', 'from', 'simple', 'vocabulary', 'to', 'simple', 'sentences', 'and', 'took', 'five', 'or', 'six', 'more', 'years', 'to', 'move', 'from', 'sentences', 'to', 'paragraphs', 'and', 'a', 'few', 'more', 'years', 'to', 'be', 'able', 'to', 'write', 'an', 'interesting', 'complete', 'short', 'story', 'on', 'your', 'own', 'We', 'want', 'you', 'to', 'learn', 'Python', 'much', 'more', 'rapidly', 'so', 'we', 'teach', 'it', 'all', 'at', 'the', 'same', 'time', 'over', 'the', 'next', 'few', 'chapters', 'But', 'it', 'is', 'like', 'learning', 'a', 'new', 'language', 'that', 'takes', 'time', 'to', 'absorb', 'and', 'understand', 'before', 'it', 'feels', 'natural', 'That', 'leads', 'to', 'some', 'confusion', 'as', 'we', 'visit', 'and', 'revisit', 'topics', 'to', 'try', 'to', 'get', 'you', 'to', 'see', 'the', 'big', 'picture', 'while', 'we', 'are', 'defining', 'the', 'tiny', 'fragments', 'that', 'make', 'up', 'that', 'big', 'picture', 'While', 'the', 'book', 'is', 'written', 'linearly', 'and', 'if', 'you', 'are', 'taking', 'a', 'course', 'it', 'will', 'progress', 'in', 'a', 'linear', 'fashion', 'don', 't', 'hesitate', 'to', 'be', 'very', 'nonlinear', 'in', 'how', 'you', 'approach', 'the', 'material', 'Look', 'forwards', 'and', 'backwards', 'and', 'read', 'with', 'a', 'light', 'touch', 'By', 'skimming', 'more', 'advanced', 'material', 'without', 'fully', 'understanding', 'the', 'details', 'you', 'can', 'get', 'a', 'better', 'understanding', 'of', 'the', 'why', 'of', 'programming', 'By', 'reviewing', 'previous', 'material', 'and', 'even', 'redoing', 'earlier', 'exercises', 'you', 'will', 'realize', 'that', 'you', 'actually', 'learned', 'a', 'lot', 'of', 'material', 'even', 'if', 'the', 'material', 'you', 'are', 'currently', 'staring', 'at', 'seems', 'a', 'bit', 'impenetrable', 'Usually', 'when', 'you', 'are', 'learning', 'your', 'first', 'programming', 'language', 'there', 'are', 'a', 'few', 'wonderful', 'Ah', 'Hah', 'moments', 'where', 'you', 'can', 'look', 'up', 'from', 'pounding', 'away', 'at', 'some', 'rock', 'with', 'a', 'hammer', 'and', 'chisel', 'and', 'step', 'away', 'and', 'see', 'that', 'you', 'are', 'indeed', 'building', 'a', 'beautiful', 'sculpture', 'If', 'something', 'seems', 'particularly', 'hard', 'there', 'is', 'usually', 'no', 'value', 'in', 'staying', 'up', 'all', 'night', 'and', 'staring', 'at', 'it', 'Take', 'a', 'break', 'take', 'a', 'nap', 'have', 'a', 'snack', 'explain', 'what', 'you', 'are', 'having', 'a', 'problem', 'with', 'to', 'someone', 'or', 'perhaps', 'your', 'dog', 'and', 'then', 'come', 'back', 'to', 'it', 'with', 'fresh', 'eyes', 'I', 'assure', 'you', 'that', 'once', 'you', 'learn', 'the', 'programming', 'concepts', 'in', 'the', 'book', 'you', 'will', 'look', 'back', 'and', 'see', 'that', 'it', 'was', 'all', 'really', 'easy', 'and', 'elegant', 'and', 'it', 'simply', 'took', 'you', 'a', 'bit', 'of', 'time', 'to', 'absorb', 'it', 'The', 'end']
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4964
76

```
<blockquote class="twitter-tweet"><p lang="en" dir="ltr">Day 20 of <a href="https://twitter.com/hashtag/100DaysOfCode?src=hash&amp;ref_src=twsrc%5Etfw">#100DaysOfCode</a> and <a href="https://twitter.com/hashtag/Python?src=hash&amp;ref_src=twsrc%5Etfw">#Python</a> <br>* Learned More About Regular expression<br>* Class on Python<br>* File Handler Class <a href="https://t.co/XGRm7UYjpC">pic.twitter.com/XGRm7UYjpC</a></p>&mdash; Durga Pokharel (@mathdurga) <a href="https://twitter.com/mathdurga/status/1349376422372995073?ref_src=twsrc%5Etfw">January 13, 2021</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>