class unittest.TestResult
This class is used to compile information about which tests have succeeded and which have failed. A TestResult object stores the results of a set of tests. The TestCase and TestSuite classes ensure that results are properly recorded; test authors do not need to worry about recording the outcome of tests. Testing frameworks built on top of unittest may want access to the TestResult object generated by running a set of tests for reporting purposes; a TestResult instance is returned by the TestRunner.run() method for this purpose. TestResult instances have the following attributes that will be of interest when inspecting the results of running a set of tests:
errors
A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents a test which raised an unexpected exception.

failures
A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents a test where a failure was explicitly signalled using the TestCase.assert*() methods.

skipped
A list containing 2-tuples of TestCase instances and strings holding the reason for skipping the test.  New in version 3.1.

expectedFailures
A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents an expected failure or error of the test case.

unexpectedSuccesses
A list containing TestCase instances that were marked as expected failures, but succeeded.

shouldStop
Set to True when the execution of tests should stop by stop().

testsRun
The total number of tests run so far.

buffer
If set to true, sys.stdout and sys.stderr will be buffered in between startTest() and stopTest() being called. Collected output will only be echoed onto the real sys.stdout and sys.stderr if the test fails or errors. Any output is also attached to the failure / error message.  New in version 3.2.

failfast
If set to true stop() will be called on the first failure or error, halting the test run.  New in version 3.2.

tb_locals
If set to true then local variables will be shown in tracebacks.  New in version 3.5.

wasSuccessful()
Return True if all tests run so far have passed, otherwise returns False.  Changed in version 3.4: Returns False if there were any unexpectedSuccesses from tests marked with the expectedFailure() decorator.

stop()
This method can be called to signal that the set of tests being run should be aborted by setting the shouldStop attribute to True. TestRunner objects should respect this flag and return without running any additional tests. For example, this feature is used by the TextTestRunner class to stop the test framework when the user signals an interrupt from the keyboard. Interactive tools which provide TestRunner implementations can use this in a similar manner.
 The following methods of the TestResult class are used to maintain the internal data structures, and may be extended in subclasses to support additional reporting requirements. This is particularly useful in building tools which support interactive reporting while tests are being run.
startTest(test)
Called when the test case test is about to be run.

stopTest(test)
Called after the test case test has been executed, regardless of the outcome.

startTestRun()
Called once before any tests are executed.  New in version 3.1.

stopTestRun()
Called once after all tests are executed.  New in version 3.1.

addError(test, err)
Called when the test case test raises an unexpected exception. err is a tuple of the form returned by sys.exc_info(): (type, value,
traceback). The default implementation appends a tuple (test, formatted_err) to the instance’s errors attribute, where formatted_err is a formatted traceback derived from err.

addFailure(test, err)
Called when the test case test signals a failure. err is a tuple of the form returned by sys.exc_info(): (type, value, traceback). The default implementation appends a tuple (test, formatted_err) to the instance’s failures attribute, where formatted_err is a formatted traceback derived from err.

addSuccess(test)
Called when the test case test succeeds. The default implementation does nothing.

addSkip(test, reason)
Called when the test case test is skipped. reason is the reason the test gave for skipping. The default implementation appends a tuple (test, reason) to the instance’s skipped attribute.

addExpectedFailure(test, err)
Called when the test case test fails or errors, but was marked with the expectedFailure() decorator. The default implementation appends a tuple (test, formatted_err) to the instance’s expectedFailures attribute, where formatted_err is a formatted traceback derived from err.

addUnexpectedSuccess(test)
Called when the test case test was marked with the expectedFailure() decorator, but succeeded. The default implementation appends the test to the instance’s unexpectedSuccesses attribute.

addSubTest(test, subtest, outcome)
Called when a subtest finishes. test is the test case corresponding to the test method. subtest is a custom TestCase instance describing the subtest. If outcome is None, the subtest succeeded. Otherwise, it failed with an exception where outcome is a tuple of the form returned by sys.exc_info(): (type, value, traceback). The default implementation does nothing when the outcome is a success, and records subtest failures as normal failures.  New in version 3.4.


addError(test, err)
Called when the test case test raises an unexpected exception. err is a tuple of the form returned by sys.exc_info(): (type, value,
traceback). The default implementation appends a tuple (test, formatted_err) to the instance’s errors attribute, where formatted_err is a formatted traceback derived from err.


addExpectedFailure(test, err)
Called when the test case test fails or errors, but was marked with the expectedFailure() decorator. The default implementation appends a tuple (test, formatted_err) to the instance’s expectedFailures attribute, where formatted_err is a formatted traceback derived from err.


addFailure(test, err)
Called when the test case test signals a failure. err is a tuple of the form returned by sys.exc_info(): (type, value, traceback). The default implementation appends a tuple (test, formatted_err) to the instance’s failures attribute, where formatted_err is a formatted traceback derived from err.


addSkip(test, reason)
Called when the test case test is skipped. reason is the reason the test gave for skipping. The default implementation appends a tuple (test, reason) to the instance’s skipped attribute.


addSubTest(test, subtest, outcome)
Called when a subtest finishes. test is the test case corresponding to the test method. subtest is a custom TestCase instance describing the subtest. If outcome is None, the subtest succeeded. Otherwise, it failed with an exception where outcome is a tuple of the form returned by sys.exc_info(): (type, value, traceback). The default implementation does nothing when the outcome is a success, and records subtest failures as normal failures.  New in version 3.4.


addSuccess(test)
Called when the test case test succeeds. The default implementation does nothing.


addUnexpectedSuccess(test)
Called when the test case test was marked with the expectedFailure() decorator, but succeeded. The default implementation appends the test to the instance’s unexpectedSuccesses attribute.


buffer
If set to true, sys.stdout and sys.stderr will be buffered in between startTest() and stopTest() being called. Collected output will only be echoed onto the real sys.stdout and sys.stderr if the test fails or errors. Any output is also attached to the failure / error message.  New in version 3.2.


errors
A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents a test which raised an unexpected exception.


expectedFailures
A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents an expected failure or error of the test case.


failfast
If set to true stop() will be called on the first failure or error, halting the test run.  New in version 3.2.


failures
A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents a test where a failure was explicitly signalled using the TestCase.assert*() methods.


shouldStop
Set to True when the execution of tests should stop by stop().


skipped
A list containing 2-tuples of TestCase instances and strings holding the reason for skipping the test.  New in version 3.1.


startTest(test)
Called when the test case test is about to be run.


startTestRun()
Called once before any tests are executed.  New in version 3.1.


stop()
This method can be called to signal that the set of tests being run should be aborted by setting the shouldStop attribute to True. TestRunner objects should respect this flag and return without running any additional tests. For example, this feature is used by the TextTestRunner class to stop the test framework when the user signals an interrupt from the keyboard. Interactive tools which provide TestRunner implementations can use this in a similar manner.


stopTest(test)
Called after the test case test has been executed, regardless of the outcome.


stopTestRun()
Called once after all tests are executed.  New in version 3.1.


tb_locals
If set to true then local variables will be shown in tracebacks.  New in version 3.5.


testsRun
The total number of tests run so far.


unexpectedSuccesses
A list containing TestCase instances that were marked as expected failures, but succeeded.


wasSuccessful()
Return True if all tests run so far have passed, otherwise returns False.  Changed in version 3.4: Returns False if there were any unexpectedSuccesses from tests marked with the expectedFailure() decorator.


class unittest.TestSuite(tests=())
This class represents an aggregation of individual test cases and test suites. The class presents the interface needed by the test runner to allow it to be run as any other test case. Running a TestSuite instance is the same as iterating over the suite, running each test individually. If tests is given, it must be an iterable of individual test cases or other test suites that will be used to build the suite initially. Additional methods are provided to add test cases and suites to the collection later on. TestSuite objects behave much like TestCase objects, except they do not actually implement a test. Instead, they are used to aggregate tests into groups of tests that should be run together. Some additional methods are available to add tests to TestSuite instances:
addTest(test)
Add a TestCase or TestSuite to the suite.

addTests(tests)
Add all the tests from an iterable of TestCase and TestSuite instances to this test suite. This is equivalent to iterating over tests, calling addTest() for each element.
 TestSuite shares the following methods with TestCase:
run(result)
Run the tests associated with this suite, collecting the result into the test result object passed as result. Note that unlike TestCase.run(), TestSuite.run() requires the result object to be passed in.

debug()
Run the tests associated with this suite without collecting the result. This allows exceptions raised by the test to be propagated to the caller and can be used to support running tests under a debugger.

countTestCases()
Return the number of tests represented by this test object, including all individual tests and sub-suites.

__iter__()
Tests grouped by a TestSuite are always accessed by iteration. Subclasses can lazily provide tests by overriding __iter__(). Note that this method may be called several times on a single suite (for example when counting tests or comparing for equality) so the tests returned by repeated iterations before TestSuite.run() must be the same for each call iteration. After TestSuite.run(), callers should not rely on the tests returned by this method unless the caller uses a subclass that overrides TestSuite._removeTestAtIndex() to preserve test references.  Changed in version 3.2: In earlier versions the TestSuite accessed tests directly rather than through iteration, so overriding __iter__() wasn’t sufficient for providing tests.   Changed in version 3.4: In earlier versions the TestSuite held references to each TestCase after TestSuite.run(). Subclasses can restore that behavior by overriding TestSuite._removeTestAtIndex().
 In the typical usage of a TestSuite object, the run() method is invoked by a TestRunner rather than by the end-user test harness.


addTest(test)
Add a TestCase or TestSuite to the suite.


addTests(tests)
Add all the tests from an iterable of TestCase and TestSuite instances to this test suite. This is equivalent to iterating over tests, calling addTest() for each element.


countTestCases()
Return the number of tests represented by this test object, including all individual tests and sub-suites.


debug()
Run the tests associated with this suite without collecting the result. This allows exceptions raised by the test to be propagated to the caller and can be used to support running tests under a debugger.


run(result)
Run the tests associated with this suite, collecting the result into the test result object passed as result. Note that unlike TestCase.run(), TestSuite.run() requires the result object to be passed in.


__iter__()
Tests grouped by a TestSuite are always accessed by iteration. Subclasses can lazily provide tests by overriding __iter__(). Note that this method may be called several times on a single suite (for example when counting tests or comparing for equality) so the tests returned by repeated iterations before TestSuite.run() must be the same for each call iteration. After TestSuite.run(), callers should not rely on the tests returned by this method unless the caller uses a subclass that overrides TestSuite._removeTestAtIndex() to preserve test references.  Changed in version 3.2: In earlier versions the TestSuite accessed tests directly rather than through iteration, so overriding __iter__() wasn’t sufficient for providing tests.   Changed in version 3.4: In earlier versions the TestSuite held references to each TestCase after TestSuite.run(). Subclasses can restore that behavior by overriding TestSuite._removeTestAtIndex().


class unittest.TextTestResult(stream, descriptions, verbosity)
A concrete implementation of TestResult used by the TextTestRunner.  New in version 3.2: This class was previously named _TextTestResult. The old name still exists as an alias but is deprecated.


class unittest.TextTestRunner(stream=None, descriptions=True, verbosity=1, failfast=False, buffer=False, resultclass=None, warnings=None, *, tb_locals=False)
A basic test runner implementation that outputs results to a stream. If stream is None, the default, sys.stderr is used as the output stream. This class has a few configurable parameters, but is essentially very simple. Graphical applications which run test suites should provide alternate implementations. Such implementations should accept **kwargs as the interface to construct runners changes when features are added to unittest. By default this runner shows DeprecationWarning, PendingDeprecationWarning, ResourceWarning and ImportWarning even if they are ignored by default. Deprecation warnings caused by deprecated unittest methods are also special-cased and, when the warning filters are 'default' or 'always', they will appear only once per-module, in order to avoid too many warning messages. This behavior can be overridden using Python’s -Wd or -Wa options (see Warning control) and leaving warnings to None.  Changed in version 3.2: Added the warnings argument.   Changed in version 3.2: The default stream is set to sys.stderr at instantiation time rather than import time.   Changed in version 3.5: Added the tb_locals parameter.
_makeResult()
This method returns the instance of TestResult used by run(). It is not intended to be called directly, but can be overridden in subclasses to provide a custom TestResult. _makeResult() instantiates the class or callable passed in the TextTestRunner constructor as the resultclass argument. It defaults to TextTestResult if no resultclass is provided. The result class is instantiated with the following arguments: stream, descriptions, verbosity

run(test)
This method is the main public interface to the TextTestRunner. This method takes a TestSuite or TestCase instance. A TestResult is created by calling _makeResult() and the test(s) are run and the results printed to stdout.


run(test)
This method is the main public interface to the TextTestRunner. This method takes a TestSuite or TestCase instance. A TestResult is created by calling _makeResult() and the test(s) are run and the results printed to stdout.


_makeResult()
This method returns the instance of TestResult used by run(). It is not intended to be called directly, but can be overridden in subclasses to provide a custom TestResult. _makeResult() instantiates the class or callable passed in the TextTestRunner constructor as the resultclass argument. It defaults to TextTestResult if no resultclass is provided. The result class is instantiated with the following arguments: stream, descriptions, verbosity


urllib — URL handling modules Source code: Lib/urllib/ urllib is a package that collects several modules for working with URLs:
urllib.request for opening and reading URLs
urllib.error containing the exceptions raised by urllib.request

urllib.parse for parsing URLs
urllib.robotparser for parsing robots.txt files


urllib.error — Exception classes raised by urllib.request Source code: Lib/urllib/error.py The urllib.error module defines the exception classes for exceptions raised by urllib.request. The base exception class is URLError. The following exceptions are raised by urllib.error as appropriate:
exception urllib.error.URLError
The handlers raise this exception (or derived exceptions) when they run into a problem. It is a subclass of OSError.
reason
The reason for this error. It can be a message string or another exception instance.
  Changed in version 3.3: URLError has been made a subclass of OSError instead of IOError.

exception urllib.error.HTTPError
Though being an exception (a subclass of URLError), an HTTPError can also function as a non-exceptional file-like return value (the same thing that urlopen() returns). This is useful when handling exotic HTTP errors, such as requests for authentication.
code
An HTTP status code as defined in RFC 2616. This numeric value corresponds to a value found in the dictionary of codes as found in http.server.BaseHTTPRequestHandler.responses.

reason
This is usually a string explaining the reason for this error.

headers
The HTTP response headers for the HTTP request that caused the HTTPError.  New in version 3.4.

exception urllib.error.ContentTooShortError(msg, content)
This exception is raised when the urlretrieve() function detects that the amount of the downloaded data is less than the expected amount (given by the Content-Length header). The content attribute stores the downloaded (and supposedly truncated) data.


exception urllib.error.ContentTooShortError(msg, content)
This exception is raised when the urlretrieve() function detects that the amount of the downloaded data is less than the expected amount (given by the Content-Length header). The content attribute stores the downloaded (and supposedly truncated) data.


exception urllib.error.HTTPError
Though being an exception (a subclass of URLError), an HTTPError can also function as a non-exceptional file-like return value (the same thing that urlopen() returns). This is useful when handling exotic HTTP errors, such as requests for authentication.
code
An HTTP status code as defined in RFC 2616. This numeric value corresponds to a value found in the dictionary of codes as found in http.server.BaseHTTPRequestHandler.responses.

reason
This is usually a string explaining the reason for this error.

headers
The HTTP response headers for the HTTP request that caused the HTTPError.  New in version 3.4.


code
An HTTP status code as defined in RFC 2616. This numeric value corresponds to a value found in the dictionary of codes as found in http.server.BaseHTTPRequestHandler.responses.


headers
The HTTP response headers for the HTTP request that caused the HTTPError.  New in version 3.4.


reason
This is usually a string explaining the reason for this error.


exception urllib.error.URLError
The handlers raise this exception (or derived exceptions) when they run into a problem. It is a subclass of OSError.
reason
The reason for this error. It can be a message string or another exception instance.
  Changed in version 3.3: URLError has been made a subclass of OSError instead of IOError.


reason
The reason for this error. It can be a message string or another exception instance.


urllib.parse — Parse URLs into components Source code: Lib/urllib/parse.py This module defines a standard interface to break Uniform Resource Locator (URL) strings up in components (addressing scheme, network location, path etc.), to combine the components back into a URL string, and to convert a “relative URL” to an absolute URL given a “base URL.” The module has been designed to match the Internet RFC on Relative Uniform Resource Locators. It supports the following URL schemes: file, ftp, gopher, hdl, http, https, imap, mailto, mms, news, nntp, prospero, rsync, rtsp, rtspu, sftp, shttp, sip, sips, snews, svn, svn+ssh, telnet, wais, ws, wss. The urllib.parse module defines functions that fall into two broad categories: URL parsing and URL quoting. These are covered in detail in the following sections. URL Parsing The URL parsing functions focus on splitting a URL string into its components, or on combining URL components into a URL string.
urllib.parse.urlparse(urlstring, scheme='', allow_fragments=True)
Parse a URL into six components, returning a 6-item named tuple. This corresponds to the general structure of a URL: scheme://netloc/path;parameters?query#fragment. Each tuple item is a string, possibly empty. The components are not broken up into smaller parts (for example, the network location is a single string), and % escapes are not expanded. The delimiters as shown above are not part of the result, except for a leading slash in the path component, which is retained if present. For example: >>> from urllib.parse import urlparse
>>> o = urlparse('http://www.cwi.nl:80/%7Eguido/Python.html')
>>> o
ParseResult(scheme='http', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> o.scheme
'http'
>>> o.port
80
>>> o.geturl()
'http://www.cwi.nl:80/%7Eguido/Python.html'
 Following the syntax specifications in RFC 1808, urlparse recognizes a netloc only if it is properly introduced by ‘//’. Otherwise the input is presumed to be a relative URL and thus to start with a path component. >>> from urllib.parse import urlparse
>>> urlparse('//www.cwi.nl:80/%7Eguido/Python.html')
ParseResult(scheme='', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> urlparse('www.cwi.nl/%7Eguido/Python.html')
ParseResult(scheme='', netloc='', path='www.cwi.nl/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> urlparse('help/Python.html')
ParseResult(scheme='', netloc='', path='help/Python.html', params='',
            query='', fragment='')
 The scheme argument gives the default addressing scheme, to be used only if the URL does not specify one. It should be the same type (text or bytes) as urlstring, except that the default value '' is always allowed, and is automatically converted to b'' if appropriate. If the allow_fragments argument is false, fragment identifiers are not recognized. Instead, they are parsed as part of the path, parameters or query component, and fragment is set to the empty string in the return value. The return value is a named tuple, which means that its items can be accessed by index or as named attributes, which are:
Attribute Index Value Value if not present
scheme 0 URL scheme specifier scheme parameter
netloc 1 Network location part empty string
path 2 Hierarchical path empty string
params 3 Parameters for last path element empty string
query 4 Query component empty string
fragment 5 Fragment identifier empty string
username  User name None
password  Password None
hostname  Host name (lower case) None
port  Port number as integer, if present None   Reading the port attribute will raise a ValueError if an invalid port is specified in the URL. See section Structured Parse Results for more information on the result object. Unmatched square brackets in the netloc attribute will raise a ValueError. Characters in the netloc attribute that decompose under NFKC normalization (as used by the IDNA encoding) into any of /, ?, #, @, or : will raise a ValueError. If the URL is decomposed before parsing, no error will be raised. As is the case with all named tuples, the subclass has a few additional methods and attributes that are particularly useful. One such method is _replace(). The _replace() method will return a new ParseResult object replacing specified fields with new values. >>> from urllib.parse import urlparse
>>> u = urlparse('//www.cwi.nl:80/%7Eguido/Python.html')
>>> u
ParseResult(scheme='', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> u._replace(scheme='http')
ParseResult(scheme='http', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
  Changed in version 3.2: Added IPv6 URL parsing capabilities.   Changed in version 3.3: The fragment is now parsed for all URL schemes (unless allow_fragment is false), in accordance with RFC 3986. Previously, a whitelist of schemes that support fragments existed.   Changed in version 3.6: Out-of-range port numbers now raise ValueError, instead of returning None.   Changed in version 3.8: Characters that affect netloc parsing under NFKC normalization will now raise ValueError.

urllib.parse.parse_qs(qs, keep_blank_values=False, strict_parsing=False, encoding='utf-8', errors='replace', max_num_fields=None, separator='&')
Parse a query string given as a string argument (data of type application/x-www-form-urlencoded). Data are returned as a dictionary. The dictionary keys are the unique query variable names and the values are lists of values for each name. The optional argument keep_blank_values is a flag indicating whether blank values in percent-encoded queries should be treated as blank strings. A true value indicates that blanks should be retained as blank strings. The default false value indicates that blank values are to be ignored and treated as if they were not included. The optional argument strict_parsing is a flag indicating what to do with parsing errors. If false (the default), errors are silently ignored. If true, errors raise a ValueError exception. The optional encoding and errors parameters specify how to decode percent-encoded sequences into Unicode characters, as accepted by the bytes.decode() method. The optional argument max_num_fields is the maximum number of fields to read. If set, then throws a ValueError if there are more than max_num_fields fields read. The optional argument separator is the symbol to use for separating the query arguments. It defaults to &. Use the urllib.parse.urlencode() function (with the doseq parameter set to True) to convert such dictionaries into query strings.  Changed in version 3.2: Add encoding and errors parameters.   Changed in version 3.8: Added max_num_fields parameter.   Changed in version 3.9.2: Added separator parameter with the default value of &. Python versions earlier than Python 3.9.2 allowed using both ; and & as query parameter separator. This has been changed to allow only a single separator key, with & as the default separator.

urllib.parse.parse_qsl(qs, keep_blank_values=False, strict_parsing=False, encoding='utf-8', errors='replace', max_num_fields=None, separator='&')
Parse a query string given as a string argument (data of type application/x-www-form-urlencoded). Data are returned as a list of name, value pairs. The optional argument keep_blank_values is a flag indicating whether blank values in percent-encoded queries should be treated as blank strings. A true value indicates that blanks should be retained as blank strings. The default false value indicates that blank values are to be ignored and treated as if they were not included. The optional argument strict_parsing is a flag indicating what to do with parsing errors. If false (the default), errors are silently ignored. If true, errors raise a ValueError exception. The optional encoding and errors parameters specify how to decode percent-encoded sequences into Unicode characters, as accepted by the bytes.decode() method. The optional argument max_num_fields is the maximum number of fields to read. If set, then throws a ValueError if there are more than max_num_fields fields read. The optional argument separator is the symbol to use for separating the query arguments. It defaults to &. Use the urllib.parse.urlencode() function to convert such lists of pairs into query strings.  Changed in version 3.2: Add encoding and errors parameters.   Changed in version 3.8: Added max_num_fields parameter.   Changed in version 3.9.2: Added separator parameter with the default value of &. Python versions earlier than Python 3.9.2 allowed using both ; and & as query parameter separator. This has been changed to allow only a single separator key, with & as the default separator.

urllib.parse.urlunparse(parts)
Construct a URL from a tuple as returned by urlparse(). The parts argument can be any six-item iterable. This may result in a slightly different, but equivalent URL, if the URL that was parsed originally had unnecessary delimiters (for example, a ? with an empty query; the RFC states that these are equivalent).

urllib.parse.urlsplit(urlstring, scheme='', allow_fragments=True)
This is similar to urlparse(), but does not split the params from the URL. This should generally be used instead of urlparse() if the more recent URL syntax allowing parameters to be applied to each segment of the path portion of the URL (see RFC 2396) is wanted. A separate function is needed to separate the path segments and parameters. This function returns a 5-item named tuple: (addressing scheme, network location, path, query, fragment identifier).
 The return value is a named tuple, its items can be accessed by index or as named attributes:
Attribute Index Value Value if not present
scheme 0 URL scheme specifier scheme parameter
netloc 1 Network location part empty string
path 2 Hierarchical path empty string
query 3 Query component empty string
fragment 4 Fragment identifier empty string
username  User name None
password  Password None
hostname  Host name (lower case) None
port  Port number as integer, if present None   Reading the port attribute will raise a ValueError if an invalid port is specified in the URL. See section Structured Parse Results for more information on the result object. Unmatched square brackets in the netloc attribute will raise a ValueError. Characters in the netloc attribute that decompose under NFKC normalization (as used by the IDNA encoding) into any of /, ?, #, @, or : will raise a ValueError. If the URL is decomposed before parsing, no error will be raised.  Changed in version 3.6: Out-of-range port numbers now raise ValueError, instead of returning None.   Changed in version 3.8: Characters that affect netloc parsing under NFKC normalization will now raise ValueError.

urllib.parse.urlunsplit(parts)
Combine the elements of a tuple as returned by urlsplit() into a complete URL as a string. The parts argument can be any five-item iterable. This may result in a slightly different, but equivalent URL, if the URL that was parsed originally had unnecessary delimiters (for example, a ? with an empty query; the RFC states that these are equivalent).

urllib.parse.urljoin(base, url, allow_fragments=True)
Construct a full (“absolute”) URL by combining a “base URL” (base) with another URL (url). Informally, this uses components of the base URL, in particular the addressing scheme, the network location and (part of) the path, to provide missing components in the relative URL. For example: >>> from urllib.parse import urljoin
>>> urljoin('http://www.cwi.nl/%7Eguido/Python.html', 'FAQ.html')
'http://www.cwi.nl/%7Eguido/FAQ.html'
 The allow_fragments argument has the same meaning and default as for urlparse().  Note If url is an absolute URL (that is, it starts with // or scheme://), the url’s hostname and/or scheme will be present in the result. For example: >>> urljoin('http://www.cwi.nl/%7Eguido/Python.html',
...         '//www.python.org/%7Eguido')
'http://www.python.org/%7Eguido'
 If you do not want that behavior, preprocess the url with urlsplit() and urlunsplit(), removing possible scheme and netloc parts.   Changed in version 3.5: Behavior updated to match the semantics defined in RFC 3986.

urllib.parse.urldefrag(url)
If url contains a fragment identifier, return a modified version of url with no fragment identifier, and the fragment identifier as a separate string. If there is no fragment identifier in url, return url unmodified and an empty string. The return value is a named tuple, its items can be accessed by index or as named attributes:
Attribute Index Value Value if not present
url 0 URL with no fragment empty string
fragment 1 Fragment identifier empty string   See section Structured Parse Results for more information on the result object.  Changed in version 3.2: Result is a structured object rather than a simple 2-tuple.

urllib.parse.unwrap(url)
Extract the url from a wrapped URL (that is, a string formatted as <URL:scheme://host/path>, <scheme://host/path>, URL:scheme://host/path or scheme://host/path). If url is not a wrapped URL, it is returned without changes.
 Parsing ASCII Encoded Bytes The URL parsing functions were originally designed to operate on character strings only. In practice, it is useful to be able to manipulate properly quoted and encoded URLs as sequences of ASCII bytes. Accordingly, the URL parsing functions in this module all operate on bytes and bytearray objects in addition to str objects. If str data is passed in, the result will also contain only str data. If bytes or bytearray data is passed in, the result will contain only bytes data. Attempting to mix str data with bytes or bytearray in a single function call will result in a TypeError being raised, while attempting to pass in non-ASCII byte values will trigger UnicodeDecodeError. To support easier conversion of result objects between str and bytes, all return values from URL parsing functions provide either an encode() method (when the result contains str data) or a decode() method (when the result contains bytes data). The signatures of these methods match those of the corresponding str and bytes methods (except that the default encoding is 'ascii' rather than 'utf-8'). Each produces a value of a corresponding type that contains either bytes data (for encode() methods) or str data (for decode() methods). Applications that need to operate on potentially improperly quoted URLs that may contain non-ASCII data will need to do their own decoding from bytes to characters before invoking the URL parsing methods. The behaviour described in this section applies only to the URL parsing functions. The URL quoting functions use their own rules when producing or consuming byte sequences as detailed in the documentation of the individual URL quoting functions.  Changed in version 3.2: URL parsing functions now accept ASCII encoded byte sequences  Structured Parse Results The result objects from the urlparse(), urlsplit() and urldefrag() functions are subclasses of the tuple type. These subclasses add the attributes listed in the documentation for those functions, the encoding and decoding support described in the previous section, as well as an additional method:
urllib.parse.SplitResult.geturl()
Return the re-combined version of the original URL as a string. This may differ from the original URL in that the scheme may be normalized to lower case and empty components may be dropped. Specifically, empty parameters, queries, and fragment identifiers will be removed. For urldefrag() results, only empty fragment identifiers will be removed. For urlsplit() and urlparse() results, all noted changes will be made to the URL returned by this method. The result of this method remains unchanged if passed back through the original parsing function: >>> from urllib.parse import urlsplit
>>> url = 'HTTP://www.Python.org/doc/#'
>>> r1 = urlsplit(url)
>>> r1.geturl()
'http://www.Python.org/doc/'
>>> r2 = urlsplit(r1.geturl())
>>> r2.geturl()
'http://www.Python.org/doc/'

 The following classes provide the implementations of the structured parse results when operating on str objects:
class urllib.parse.DefragResult(url, fragment)
Concrete class for urldefrag() results containing str data. The encode() method returns a DefragResultBytes instance.  New in version 3.2.

class urllib.parse.ParseResult(scheme, netloc, path, params, query, fragment)
Concrete class for urlparse() results containing str data. The encode() method returns a ParseResultBytes instance.

class urllib.parse.SplitResult(scheme, netloc, path, query, fragment)
Concrete class for urlsplit() results containing str data. The encode() method returns a SplitResultBytes instance.
 The following classes provide the implementations of the parse results when operating on bytes or bytearray objects:
class urllib.parse.DefragResultBytes(url, fragment)
Concrete class for urldefrag() results containing bytes data. The decode() method returns a DefragResult instance.  New in version 3.2.

class urllib.parse.ParseResultBytes(scheme, netloc, path, params, query, fragment)
Concrete class for urlparse() results containing bytes data. The decode() method returns a ParseResult instance.  New in version 3.2.

class urllib.parse.SplitResultBytes(scheme, netloc, path, query, fragment)
Concrete class for urlsplit() results containing bytes data. The decode() method returns a SplitResult instance.  New in version 3.2.
 URL Quoting The URL quoting functions focus on taking program data and making it safe for use as URL components by quoting special characters and appropriately encoding non-ASCII text. They also support reversing these operations to recreate the original data from the contents of a URL component if that task isn’t already covered by the URL parsing functions above.
urllib.parse.quote(string, safe='/', encoding=None, errors=None)
Replace special characters in string using the %xx escape. Letters, digits, and the characters '_.-~' are never quoted. By default, this function is intended for quoting the path section of a URL. The optional safe parameter specifies additional ASCII characters that should not be quoted — its default value is '/'. string may be either a str or a bytes object.  Changed in version 3.7: Moved from RFC 2396 to RFC 3986 for quoting URL strings. “~” is now included in the set of unreserved characters.  The optional encoding and errors parameters specify how to deal with non-ASCII characters, as accepted by the str.encode() method. encoding defaults to 'utf-8'. errors defaults to 'strict', meaning unsupported characters raise a UnicodeEncodeError. encoding and errors must not be supplied if string is a bytes, or a TypeError is raised. Note that quote(string, safe, encoding, errors) is equivalent to quote_from_bytes(string.encode(encoding, errors), safe). Example: quote('/El Niño/') yields '/El%20Ni%C3%B1o/'.

urllib.parse.quote_plus(string, safe='', encoding=None, errors=None)
Like quote(), but also replace spaces with plus signs, as required for quoting HTML form values when building up a query string to go into a URL. Plus signs in the original string are escaped unless they are included in safe. It also does not have safe default to '/'. Example: quote_plus('/El Niño/') yields '%2FEl+Ni%C3%B1o%2F'.

urllib.parse.quote_from_bytes(bytes, safe='/')
Like quote(), but accepts a bytes object rather than a str, and does not perform string-to-bytes encoding. Example: quote_from_bytes(b'a&\xef') yields 'a%26%EF'.

urllib.parse.unquote(string, encoding='utf-8', errors='replace')
Replace %xx escapes with their single-character equivalent. The optional encoding and errors parameters specify how to decode percent-encoded sequences into Unicode characters, as accepted by the bytes.decode() method. string may be either a str or a bytes object. encoding defaults to 'utf-8'. errors defaults to 'replace', meaning invalid sequences are replaced by a placeholder character. Example: unquote('/El%20Ni%C3%B1o/') yields '/El Niño/'.  Changed in version 3.9: string parameter supports bytes and str objects (previously only str).

urllib.parse.unquote_plus(string, encoding='utf-8', errors='replace')
Like unquote(), but also replace plus signs with spaces, as required for unquoting HTML form values. string must be a str. Example: unquote_plus('/El+Ni%C3%B1o/') yields '/El Niño/'.

urllib.parse.unquote_to_bytes(string)
Replace %xx escapes with their single-octet equivalent, and return a bytes object. string may be either a str or a bytes object. If it is a str, unescaped non-ASCII characters in string are encoded into UTF-8 bytes. Example: unquote_to_bytes('a%26%EF') yields b'a&\xef'.

urllib.parse.urlencode(query, doseq=False, safe='', encoding=None, errors=None, quote_via=quote_plus)
Convert a mapping object or a sequence of two-element tuples, which may contain str or bytes objects, to a percent-encoded ASCII text string. If the resultant string is to be used as a data for POST operation with the urlopen() function, then it should be encoded to bytes, otherwise it would result in a TypeError. The resulting string is a series of key=value pairs separated by '&' characters, where both key and value are quoted using the quote_via function. By default, quote_plus() is used to quote the values, which means spaces are quoted as a '+' character and ‘/’ characters are encoded as %2F, which follows the standard for GET requests (application/x-www-form-urlencoded). An alternate function that can be passed as quote_via is quote(), which will encode spaces as %20 and not encode ‘/’ characters. For maximum control of what is quoted, use quote and specify a value for safe. When a sequence of two-element tuples is used as the query argument, the first element of each tuple is a key and the second is a value. The value element in itself can be a sequence and in that case, if the optional parameter doseq evaluates to True, individual key=value pairs separated by '&' are generated for each element of the value sequence for the key. The order of parameters in the encoded string will match the order of parameter tuples in the sequence. The safe, encoding, and errors parameters are passed down to quote_via (the encoding and errors parameters are only passed when a query element is a str). To reverse this encoding process, parse_qs() and parse_qsl() are provided in this module to parse query strings into Python data structures. Refer to urllib examples to find out how the urllib.parse.urlencode() method can be used for generating the query string of a URL or data for a POST request.  Changed in version 3.2: query supports bytes and string objects.   New in version 3.5: quote_via parameter.
  See also
RFC 3986 - Uniform Resource Identifiers

This is the current standard (STD66). Any changes to urllib.parse module should conform to this. Certain deviations could be observed, which are mostly for backward compatibility purposes and for certain de-facto parsing requirements as commonly observed in major browsers.
RFC 2732 - Format for Literal IPv6 Addresses in URL’s.

This specifies the parsing requirements of IPv6 URLs.
RFC 2396 - Uniform Resource Identifiers (URI): Generic Syntax

Document describing the generic syntactic requirements for both Uniform Resource Names (URNs) and Uniform Resource Locators (URLs).
RFC 2368 - The mailto URL scheme.

Parsing requirements for mailto URL schemes.
RFC 1808 - Relative Uniform Resource Locators

This Request For Comments includes the rules for joining an absolute and a relative URL, including a fair number of “Abnormal Examples” which govern the treatment of border cases.
RFC 1738 - Uniform Resource Locators (URL)

This specifies the formal syntax and semantics of absolute URLs.


class urllib.parse.DefragResult(url, fragment)
Concrete class for urldefrag() results containing str data. The encode() method returns a DefragResultBytes instance.  New in version 3.2.


class urllib.parse.DefragResultBytes(url, fragment)
Concrete class for urldefrag() results containing bytes data. The decode() method returns a DefragResult instance.  New in version 3.2.


class urllib.parse.ParseResult(scheme, netloc, path, params, query, fragment)
Concrete class for urlparse() results containing str data. The encode() method returns a ParseResultBytes instance.


class urllib.parse.ParseResultBytes(scheme, netloc, path, params, query, fragment)
Concrete class for urlparse() results containing bytes data. The decode() method returns a ParseResult instance.  New in version 3.2.


urllib.parse.parse_qs(qs, keep_blank_values=False, strict_parsing=False, encoding='utf-8', errors='replace', max_num_fields=None, separator='&')
Parse a query string given as a string argument (data of type application/x-www-form-urlencoded). Data are returned as a dictionary. The dictionary keys are the unique query variable names and the values are lists of values for each name. The optional argument keep_blank_values is a flag indicating whether blank values in percent-encoded queries should be treated as blank strings. A true value indicates that blanks should be retained as blank strings. The default false value indicates that blank values are to be ignored and treated as if they were not included. The optional argument strict_parsing is a flag indicating what to do with parsing errors. If false (the default), errors are silently ignored. If true, errors raise a ValueError exception. The optional encoding and errors parameters specify how to decode percent-encoded sequences into Unicode characters, as accepted by the bytes.decode() method. The optional argument max_num_fields is the maximum number of fields to read. If set, then throws a ValueError if there are more than max_num_fields fields read. The optional argument separator is the symbol to use for separating the query arguments. It defaults to &. Use the urllib.parse.urlencode() function (with the doseq parameter set to True) to convert such dictionaries into query strings.  Changed in version 3.2: Add encoding and errors parameters.   Changed in version 3.8: Added max_num_fields parameter.   Changed in version 3.9.2: Added separator parameter with the default value of &. Python versions earlier than Python 3.9.2 allowed using both ; and & as query parameter separator. This has been changed to allow only a single separator key, with & as the default separator.


urllib.parse.parse_qsl(qs, keep_blank_values=False, strict_parsing=False, encoding='utf-8', errors='replace', max_num_fields=None, separator='&')
Parse a query string given as a string argument (data of type application/x-www-form-urlencoded). Data are returned as a list of name, value pairs. The optional argument keep_blank_values is a flag indicating whether blank values in percent-encoded queries should be treated as blank strings. A true value indicates that blanks should be retained as blank strings. The default false value indicates that blank values are to be ignored and treated as if they were not included. The optional argument strict_parsing is a flag indicating what to do with parsing errors. If false (the default), errors are silently ignored. If true, errors raise a ValueError exception. The optional encoding and errors parameters specify how to decode percent-encoded sequences into Unicode characters, as accepted by the bytes.decode() method. The optional argument max_num_fields is the maximum number of fields to read. If set, then throws a ValueError if there are more than max_num_fields fields read. The optional argument separator is the symbol to use for separating the query arguments. It defaults to &. Use the urllib.parse.urlencode() function to convert such lists of pairs into query strings.  Changed in version 3.2: Add encoding and errors parameters.   Changed in version 3.8: Added max_num_fields parameter.   Changed in version 3.9.2: Added separator parameter with the default value of &. Python versions earlier than Python 3.9.2 allowed using both ; and & as query parameter separator. This has been changed to allow only a single separator key, with & as the default separator.


urllib.parse.quote(string, safe='/', encoding=None, errors=None)
Replace special characters in string using the %xx escape. Letters, digits, and the characters '_.-~' are never quoted. By default, this function is intended for quoting the path section of a URL. The optional safe parameter specifies additional ASCII characters that should not be quoted — its default value is '/'. string may be either a str or a bytes object.  Changed in version 3.7: Moved from RFC 2396 to RFC 3986 for quoting URL strings. “~” is now included in the set of unreserved characters.  The optional encoding and errors parameters specify how to deal with non-ASCII characters, as accepted by the str.encode() method. encoding defaults to 'utf-8'. errors defaults to 'strict', meaning unsupported characters raise a UnicodeEncodeError. encoding and errors must not be supplied if string is a bytes, or a TypeError is raised. Note that quote(string, safe, encoding, errors) is equivalent to quote_from_bytes(string.encode(encoding, errors), safe). Example: quote('/El Niño/') yields '/El%20Ni%C3%B1o/'.


urllib.parse.quote_from_bytes(bytes, safe='/')
Like quote(), but accepts a bytes object rather than a str, and does not perform string-to-bytes encoding. Example: quote_from_bytes(b'a&\xef') yields 'a%26%EF'.


urllib.parse.quote_plus(string, safe='', encoding=None, errors=None)
Like quote(), but also replace spaces with plus signs, as required for quoting HTML form values when building up a query string to go into a URL. Plus signs in the original string are escaped unless they are included in safe. It also does not have safe default to '/'. Example: quote_plus('/El Niño/') yields '%2FEl+Ni%C3%B1o%2F'.


class urllib.parse.SplitResult(scheme, netloc, path, query, fragment)
Concrete class for urlsplit() results containing str data. The encode() method returns a SplitResultBytes instance.


class urllib.parse.SplitResultBytes(scheme, netloc, path, query, fragment)
Concrete class for urlsplit() results containing bytes data. The decode() method returns a SplitResult instance.  New in version 3.2.


urllib.parse.unquote(string, encoding='utf-8', errors='replace')
Replace %xx escapes with their single-character equivalent. The optional encoding and errors parameters specify how to decode percent-encoded sequences into Unicode characters, as accepted by the bytes.decode() method. string may be either a str or a bytes object. encoding defaults to 'utf-8'. errors defaults to 'replace', meaning invalid sequences are replaced by a placeholder character. Example: unquote('/El%20Ni%C3%B1o/') yields '/El Niño/'.  Changed in version 3.9: string parameter supports bytes and str objects (previously only str).


urllib.parse.unquote_plus(string, encoding='utf-8', errors='replace')
Like unquote(), but also replace plus signs with spaces, as required for unquoting HTML form values. string must be a str. Example: unquote_plus('/El+Ni%C3%B1o/') yields '/El Niño/'.


urllib.parse.unquote_to_bytes(string)
Replace %xx escapes with their single-octet equivalent, and return a bytes object. string may be either a str or a bytes object. If it is a str, unescaped non-ASCII characters in string are encoded into UTF-8 bytes. Example: unquote_to_bytes('a%26%EF') yields b'a&\xef'.


urllib.parse.unwrap(url)
Extract the url from a wrapped URL (that is, a string formatted as <URL:scheme://host/path>, <scheme://host/path>, URL:scheme://host/path or scheme://host/path). If url is not a wrapped URL, it is returned without changes.


urllib.parse.urldefrag(url)
If url contains a fragment identifier, return a modified version of url with no fragment identifier, and the fragment identifier as a separate string. If there is no fragment identifier in url, return url unmodified and an empty string. The return value is a named tuple, its items can be accessed by index or as named attributes:
Attribute Index Value Value if not present
url 0 URL with no fragment empty string
fragment 1 Fragment identifier empty string   See section Structured Parse Results for more information on the result object.  Changed in version 3.2: Result is a structured object rather than a simple 2-tuple.


urllib.parse.urlencode(query, doseq=False, safe='', encoding=None, errors=None, quote_via=quote_plus)
Convert a mapping object or a sequence of two-element tuples, which may contain str or bytes objects, to a percent-encoded ASCII text string. If the resultant string is to be used as a data for POST operation with the urlopen() function, then it should be encoded to bytes, otherwise it would result in a TypeError. The resulting string is a series of key=value pairs separated by '&' characters, where both key and value are quoted using the quote_via function. By default, quote_plus() is used to quote the values, which means spaces are quoted as a '+' character and ‘/’ characters are encoded as %2F, which follows the standard for GET requests (application/x-www-form-urlencoded). An alternate function that can be passed as quote_via is quote(), which will encode spaces as %20 and not encode ‘/’ characters. For maximum control of what is quoted, use quote and specify a value for safe. When a sequence of two-element tuples is used as the query argument, the first element of each tuple is a key and the second is a value. The value element in itself can be a sequence and in that case, if the optional parameter doseq evaluates to True, individual key=value pairs separated by '&' are generated for each element of the value sequence for the key. The order of parameters in the encoded string will match the order of parameter tuples in the sequence. The safe, encoding, and errors parameters are passed down to quote_via (the encoding and errors parameters are only passed when a query element is a str). To reverse this encoding process, parse_qs() and parse_qsl() are provided in this module to parse query strings into Python data structures. Refer to urllib examples to find out how the urllib.parse.urlencode() method can be used for generating the query string of a URL or data for a POST request.  Changed in version 3.2: query supports bytes and string objects.   New in version 3.5: quote_via parameter.


urllib.parse.urljoin(base, url, allow_fragments=True)
Construct a full (“absolute”) URL by combining a “base URL” (base) with another URL (url). Informally, this uses components of the base URL, in particular the addressing scheme, the network location and (part of) the path, to provide missing components in the relative URL. For example: >>> from urllib.parse import urljoin
>>> urljoin('http://www.cwi.nl/%7Eguido/Python.html', 'FAQ.html')
'http://www.cwi.nl/%7Eguido/FAQ.html'
 The allow_fragments argument has the same meaning and default as for urlparse().  Note If url is an absolute URL (that is, it starts with // or scheme://), the url’s hostname and/or scheme will be present in the result. For example: >>> urljoin('http://www.cwi.nl/%7Eguido/Python.html',
...         '//www.python.org/%7Eguido')
'http://www.python.org/%7Eguido'
 If you do not want that behavior, preprocess the url with urlsplit() and urlunsplit(), removing possible scheme and netloc parts.   Changed in version 3.5: Behavior updated to match the semantics defined in RFC 3986.


urllib.parse.SplitResult.geturl()
Return the re-combined version of the original URL as a string. This may differ from the original URL in that the scheme may be normalized to lower case and empty components may be dropped. Specifically, empty parameters, queries, and fragment identifiers will be removed. For urldefrag() results, only empty fragment identifiers will be removed. For urlsplit() and urlparse() results, all noted changes will be made to the URL returned by this method. The result of this method remains unchanged if passed back through the original parsing function: >>> from urllib.parse import urlsplit
>>> url = 'HTTP://www.Python.org/doc/#'
>>> r1 = urlsplit(url)
>>> r1.geturl()
'http://www.Python.org/doc/'
>>> r2 = urlsplit(r1.geturl())
>>> r2.geturl()
'http://www.Python.org/doc/'


urllib.parse.urlparse(urlstring, scheme='', allow_fragments=True)
Parse a URL into six components, returning a 6-item named tuple. This corresponds to the general structure of a URL: scheme://netloc/path;parameters?query#fragment. Each tuple item is a string, possibly empty. The components are not broken up into smaller parts (for example, the network location is a single string), and % escapes are not expanded. The delimiters as shown above are not part of the result, except for a leading slash in the path component, which is retained if present. For example: >>> from urllib.parse import urlparse
>>> o = urlparse('http://www.cwi.nl:80/%7Eguido/Python.html')
>>> o
ParseResult(scheme='http', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> o.scheme
'http'
>>> o.port
80
>>> o.geturl()
'http://www.cwi.nl:80/%7Eguido/Python.html'
 Following the syntax specifications in RFC 1808, urlparse recognizes a netloc only if it is properly introduced by ‘//’. Otherwise the input is presumed to be a relative URL and thus to start with a path component. >>> from urllib.parse import urlparse
>>> urlparse('//www.cwi.nl:80/%7Eguido/Python.html')
ParseResult(scheme='', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> urlparse('www.cwi.nl/%7Eguido/Python.html')
ParseResult(scheme='', netloc='', path='www.cwi.nl/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> urlparse('help/Python.html')
ParseResult(scheme='', netloc='', path='help/Python.html', params='',
            query='', fragment='')
 The scheme argument gives the default addressing scheme, to be used only if the URL does not specify one. It should be the same type (text or bytes) as urlstring, except that the default value '' is always allowed, and is automatically converted to b'' if appropriate. If the allow_fragments argument is false, fragment identifiers are not recognized. Instead, they are parsed as part of the path, parameters or query component, and fragment is set to the empty string in the return value. The return value is a named tuple, which means that its items can be accessed by index or as named attributes, which are:
Attribute Index Value Value if not present
scheme 0 URL scheme specifier scheme parameter
netloc 1 Network location part empty string
path 2 Hierarchical path empty string
params 3 Parameters for last path element empty string
query 4 Query component empty string
fragment 5 Fragment identifier empty string
username  User name None
password  Password None
hostname  Host name (lower case) None
port  Port number as integer, if present None   Reading the port attribute will raise a ValueError if an invalid port is specified in the URL. See section Structured Parse Results for more information on the result object. Unmatched square brackets in the netloc attribute will raise a ValueError. Characters in the netloc attribute that decompose under NFKC normalization (as used by the IDNA encoding) into any of /, ?, #, @, or : will raise a ValueError. If the URL is decomposed before parsing, no error will be raised. As is the case with all named tuples, the subclass has a few additional methods and attributes that are particularly useful. One such method is _replace(). The _replace() method will return a new ParseResult object replacing specified fields with new values. >>> from urllib.parse import urlparse
>>> u = urlparse('//www.cwi.nl:80/%7Eguido/Python.html')
>>> u
ParseResult(scheme='', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
>>> u._replace(scheme='http')
ParseResult(scheme='http', netloc='www.cwi.nl:80', path='/%7Eguido/Python.html',
            params='', query='', fragment='')
  Changed in version 3.2: Added IPv6 URL parsing capabilities.   Changed in version 3.3: The fragment is now parsed for all URL schemes (unless allow_fragment is false), in accordance with RFC 3986. Previously, a whitelist of schemes that support fragments existed.   Changed in version 3.6: Out-of-range port numbers now raise ValueError, instead of returning None.   Changed in version 3.8: Characters that affect netloc parsing under NFKC normalization will now raise ValueError.


urllib.parse.urlsplit(urlstring, scheme='', allow_fragments=True)
This is similar to urlparse(), but does not split the params from the URL. This should generally be used instead of urlparse() if the more recent URL syntax allowing parameters to be applied to each segment of the path portion of the URL (see RFC 2396) is wanted. A separate function is needed to separate the path segments and parameters. This function returns a 5-item named tuple: (addressing scheme, network location, path, query, fragment identifier).
 The return value is a named tuple, its items can be accessed by index or as named attributes:
Attribute Index Value Value if not present
scheme 0 URL scheme specifier scheme parameter
netloc 1 Network location part empty string
path 2 Hierarchical path empty string
query 3 Query component empty string
fragment 4 Fragment identifier empty string
username  User name None
password  Password None
hostname  Host name (lower case) None
port  Port number as integer, if present None   Reading the port attribute will raise a ValueError if an invalid port is specified in the URL. See section Structured Parse Results for more information on the result object. Unmatched square brackets in the netloc attribute will raise a ValueError. Characters in the netloc attribute that decompose under NFKC normalization (as used by the IDNA encoding) into any of /, ?, #, @, or : will raise a ValueError. If the URL is decomposed before parsing, no error will be raised.  Changed in version 3.6: Out-of-range port numbers now raise ValueError, instead of returning None.   Changed in version 3.8: Characters that affect netloc parsing under NFKC normalization will now raise ValueError.


urllib.parse.urlunparse(parts)
Construct a URL from a tuple as returned by urlparse(). The parts argument can be any six-item iterable. This may result in a slightly different, but equivalent URL, if the URL that was parsed originally had unnecessary delimiters (for example, a ? with an empty query; the RFC states that these are equivalent).


urllib.parse.urlunsplit(parts)
Combine the elements of a tuple as returned by urlsplit() into a complete URL as a string. The parts argument can be any five-item iterable. This may result in a slightly different, but equivalent URL, if the URL that was parsed originally had unnecessary delimiters (for example, a ? with an empty query; the RFC states that these are equivalent).