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Smith <eric at trueblade.com></dd> <dt class="field-odd">Status:</dt> <dd class="field-odd"><abbr title="Accepted and implementation complete, or no longer active">Final</abbr></dd> <dt class="field-even">Type:</dt> <dd class="field-even"><abbr title="Normative PEP with a new feature for Python, implementation change for CPython or interoperability standard for the ecosystem">Standards Track</abbr></dd> <dt class="field-odd">Created:</dt> <dd class="field-odd">19-Mar-2020</dd> <dt class="field-even">Python-Version:</dt> <dd class="field-even">3.9</dd> <dt class="field-odd">Post-History:</dt> <dd class="field-odd">20-Mar-2020</dd> </dl> <hr class="docutils" /> <section id="contents"> <details><summary>Table of Contents</summary><ul class="simple"> <li><a class="reference internal" href="#abstract">Abstract</a></li> <li><a class="reference internal" href="#rationale">Rationale</a></li> <li><a class="reference internal" href="#specification">Specification</a></li> <li><a class="reference internal" href="#motivating-examples-from-the-python-standard-library">Motivating examples from the Python standard library</a><ul> <li><a class="reference internal" href="#find-recursionlimit-py">find_recursionlimit.py</a></li> <li><a class="reference internal" href="#deccheck-py">deccheck.py</a></li> <li><a class="reference internal" href="#cookiejar-py">cookiejar.py</a></li> <li><a class="reference internal" href="#test-i18n-py">test_i18n.py</a></li> </ul> </li> <li><a class="reference internal" href="#rejected-ideas">Rejected Ideas</a><ul> <li><a class="reference internal" href="#expand-the-lstrip-and-rstrip-apis">Expand the lstrip and rstrip APIs</a></li> <li><a class="reference internal" href="#remove-multiple-copies-of-a-prefix">Remove multiple copies of a prefix</a></li> <li><a class="reference internal" href="#raising-an-exception-when-not-found">Raising an exception when not found</a></li> <li><a class="reference internal" href="#accepting-a-tuple-of-affixes">Accepting a tuple of affixes</a></li> <li><a class="reference internal" href="#alternative-method-names">Alternative Method Names</a></li> </ul> </li> <li><a class="reference internal" href="#how-to-teach-this">How to Teach This</a></li> <li><a class="reference internal" href="#reference-implementation">Reference Implementation</a></li> <li><a class="reference internal" href="#history-of-major-revisions">History of Major revisions</a></li> <li><a class="reference internal" href="#references">References</a></li> <li><a class="reference internal" href="#copyright">Copyright</a></li> </ul> </details></section> <section id="abstract"> <h2><a class="toc-backref" href="#abstract" role="doc-backlink">Abstract</a></h2> This is a proposal to add two new methods, <code class="docutils literal notranslate">removeprefix()</code> and <code class="docutils literal notranslate">removesuffix()</code>, to the APIs of Python’s various string objects. These methods would remove a prefix or suffix (respectively) from a string, if present, and would be added to Unicode <code class="docutils literal notranslate">str</code> objects, binary <code class="docutils literal notranslate">bytes</code> and <code class="docutils literal notranslate">bytearray</code> objects, and <code class="docutils literal notranslate">collections.UserString</code>. </section> <section id="rationale"> <h2><a class="toc-backref" href="#rationale" role="doc-backlink">Rationale</a></h2> There have been repeated issues on Python-Ideas <a class="footnote-reference brackets" href="#pyid" id="id1">[2]</a> <a class="footnote-reference brackets" href="#id10" id="id2">[3]</a>, Python-Dev <a class="footnote-reference brackets" href="#id11" id="id3">[4]</a> <a class="footnote-reference brackets" href="#id12" id="id4">[5]</a> <a class="footnote-reference brackets" href="#id13" id="id5">[6]</a> <a class="footnote-reference brackets" href="#id14" id="id6">[7]</a>, the Bug Tracker, and StackOverflow <a class="footnote-reference brackets" href="#confusion" id="id7">[8]</a>, related to user confusion about the existing <code class="docutils literal notranslate">str.lstrip</code> and <code class="docutils literal notranslate">str.rstrip</code> methods. These users are typically expecting the behavior of <code class="docutils literal notranslate">removeprefix</code> and <code class="docutils literal notranslate">removesuffix</code>, but they are surprised that the parameter for <code class="docutils literal notranslate">lstrip</code> is interpreted as a set of characters, not a substring. This repeated issue is evidence that these methods are useful. The new methods allow a cleaner redirection of users to the desired behavior. As another testimonial for the usefulness of these methods, several users on Python-Ideas <a class="footnote-reference brackets" href="#pyid" id="id8">[2]</a> reported frequently including similar functions in their code for productivity. The implementation often contained subtle mistakes regarding the handling of the empty string, so a well-tested built-in method would be useful. The existing solutions for creating the desired behavior are to either implement the methods as in the <a class="reference internal" href="#specification">Specification</a> below, or to use regular expressions as in the expression <code class="docutils literal notranslate">re.sub('^' + re.escape(prefix), '', s)</code>, which is less discoverable, requires a module import, and results in less readable code. </section> <section id="specification"> <h2><a class="toc-backref" href="#specification" role="doc-backlink">Specification</a></h2> The builtin <code class="docutils literal notranslate">str</code> class will gain two new methods which will behave as follows when <code class="docutils literal notranslate">type(self) is type(prefix) is type(suffix) is str</code>: <div class="highlight-default notranslate"><div class="highlight"><pre>def removeprefix(self: str, prefix: str, /) -> str: if self.startswith(prefix): return self[len(prefix):] else: return self[:] def removesuffix(self: str, suffix: str, /) -> str: # suffix='' should not call self[:-0]. if suffix and self.endswith(suffix): return self[:-len(suffix)] else: return self[:] </pre></div> </div> When the arguments are instances of <code class="docutils literal notranslate">str</code> subclasses, the methods should behave as though those arguments were first coerced to base <code class="docutils literal notranslate">str</code> objects, and the return value should always be a base <code class="docutils literal notranslate">str</code>. Methods with the corresponding semantics will be added to the builtin <code class="docutils literal notranslate">bytes</code> and <code class="docutils literal notranslate">bytearray</code> objects. If <code class="docutils literal notranslate">b</code> is either a <code class="docutils literal notranslate">bytes</code> or <code class="docutils literal notranslate">bytearray</code> object, then <code class="docutils literal notranslate">b.removeprefix()</code> and <code class="docutils literal notranslate">b.removesuffix()</code> will accept any bytes-like object as an argument. The two methods will also be added to <code class="docutils literal notranslate">collections.UserString</code>, with similar behavior. </section> <section id="motivating-examples-from-the-python-standard-library"> <h2><a class="toc-backref" href="#motivating-examples-from-the-python-standard-library" role="doc-backlink">Motivating examples from the Python standard library</a></h2> The examples below demonstrate how the proposed methods can make code one or more of the following: <ol class="arabic"> <li>Less fragile:The code will not depend on the user to count the length of a literal. </li> <li>More performant:The code does not require a call to the Python built-in <code class="docutils literal notranslate">len</code> function nor to the more expensive <code class="docutils literal notranslate">str.replace()</code> method. </li> <li>More descriptive:The methods give a higher-level API for code readability as opposed to the traditional method of string slicing. </li> </ol> <section id="find-recursionlimit-py"> <h3><a class="toc-backref" href="#find-recursionlimit-py" role="doc-backlink">find_recursionlimit.py</a></h3> <ul> <li>Current:<div class="highlight-default notranslate"><div class="highlight"><pre>if test_func_name.startswith("test_"): print(test_func_name[5:]) else: print(test_func_name) </pre></div> </div> </li> <li>Improved:<div class="highlight-default notranslate"><div class="highlight"><pre>print(test_func_name.removeprefix("test_")) </pre></div> </div> </li> </ul> </section> <section id="deccheck-py"> <h3><a class="toc-backref" href="#deccheck-py" role="doc-backlink">deccheck.py</a></h3> This is an interesting case because the author chose to use the <code class="docutils literal notranslate">str.replace</code> method in a situation where only a prefix was intended to be removed. <ul> <li>Current:<div class="highlight-default notranslate"><div class="highlight"><pre>if funcname.startswith("context."): self.funcname = funcname.replace("context.", "") self.contextfunc = True else: self.funcname = funcname self.contextfunc = False </pre></div> </div> </li> <li>Improved:<div class="highlight-default notranslate"><div class="highlight"><pre>if funcname.startswith("context."): self.funcname = funcname.removeprefix("context.") self.contextfunc = True else: self.funcname = funcname self.contextfunc = False </pre></div> </div> </li> <li>Arguably further improved:<div class="highlight-default notranslate"><div class="highlight"><pre>self.contextfunc = funcname.startswith("context.") self.funcname = funcname.removeprefix("context.") </pre></div> </div> </li> </ul> </section> <section id="cookiejar-py"> <h3><a class="toc-backref" href="#cookiejar-py" role="doc-backlink">cookiejar.py</a></h3> <ul> <li>Current:<div class="highlight-default notranslate"><div class="highlight"><pre>def strip_quotes(text): if text.startswith('"'): text = text[1:] if text.endswith('"'): text = text[:-1] return text </pre></div> </div> </li> <li>Improved:<div class="highlight-default notranslate"><div class="highlight"><pre>def strip_quotes(text): return text.removeprefix('"').removesuffix('"') </pre></div> </div> </li> </ul> </section> <section id="test-i18n-py"> <h3><a class="toc-backref" href="#test-i18n-py" role="doc-backlink">test_i18n.py</a></h3> <ul> <li>Current:<div class="highlight-default notranslate"><div class="highlight"><pre>creationDate = header['POT-Creation-Date'] # peel off the escaped newline at the end of string if creationDate.endswith('\\n'): creationDate = creationDate[:-len('\\n')] </pre></div> </div> </li> <li>Improved:<div class="highlight-default notranslate"><div class="highlight"><pre>creationDate = header['POT-Creation-Date'].removesuffix('\\n') </pre></div> </div> </li> </ul> There were many other such examples in the stdlib. </section> </section> <section id="rejected-ideas"> <h2><a class="toc-backref" href="#rejected-ideas" role="doc-backlink">Rejected Ideas</a></h2> <section id="expand-the-lstrip-and-rstrip-apis"> <h3><a class="toc-backref" href="#expand-the-lstrip-and-rstrip-apis" role="doc-backlink">Expand the lstrip and rstrip APIs</a></h3> Because <code class="docutils literal notranslate">lstrip</code> takes a string as its argument, it could be viewed as taking an iterable of length-1 strings. The API could, therefore, be generalized to accept any iterable of strings, which would be successively removed as prefixes. While this behavior would be consistent, it would not be obvious for users to have to call <code class="docutils literal notranslate">'foobar'.lstrip(('foo',))</code> for the common use case of a single prefix. </section> <section id="remove-multiple-copies-of-a-prefix"> <h3><a class="toc-backref" href="#remove-multiple-copies-of-a-prefix" role="doc-backlink">Remove multiple copies of a prefix</a></h3> This is the behavior that would be consistent with the aforementioned expansion of the <code class="docutils literal notranslate">lstrip</code>/<code class="docutils literal notranslate">rstrip</code> API – repeatedly applying the function until the argument is unchanged. This behavior is attainable from the proposed behavior via by the following: <div class="highlight-default notranslate"><div class="highlight"><pre>>>> s = 'Foo' * 100 + 'Bar' >>> prefix = 'Foo' >>> while s.startswith(prefix): s = s.removeprefix(prefix) >>> s 'Bar' </pre></div> </div> </section> <section id="raising-an-exception-when-not-found"> <h3><a class="toc-backref" href="#raising-an-exception-when-not-found" role="doc-backlink">Raising an exception when not found</a></h3> There was a suggestion that <code class="docutils literal notranslate">s.removeprefix(pre)</code> should raise an exception if <code class="docutils literal notranslate">not s.startswith(pre)</code>. However, this does not match with the behavior and feel of other string methods. There could be <code class="docutils literal notranslate">required=False</code> keyword added, but this violates the KISS principle. </section> <section id="accepting-a-tuple-of-affixes"> <h3><a class="toc-backref" href="#accepting-a-tuple-of-affixes" role="doc-backlink">Accepting a tuple of affixes</a></h3> It could be convenient to write the <code class="docutils literal notranslate">test_concurrent_futures.py</code> example above as <code class="docutils literal notranslate">name.removesuffix(('Mixin', 'Tests', 'Test'))</code>, so there was a suggestion that the new methods be able to take a tuple of strings as an argument, similar to the <code class="docutils literal notranslate">startswith()</code> API. Within the tuple, only the first matching affix would be removed. This was rejected on the following grounds: <ul class="simple"> <li>This behavior can be surprising or visually confusing, especially when one prefix is empty or is a substring of another prefix, as in <code class="docutils literal notranslate">'FooBar'.removeprefix(('', 'Foo')) == 'FooBar'</code> or <code class="docutils literal notranslate">'FooBar text'.removeprefix(('Foo', 'FooBar ')) == 'Bar text'</code>.</li> <li>The API for <code class="docutils literal notranslate">str.replace()</code> only accepts a single pair of replacement strings, but has stood the test of time by refusing the temptation to guess in the face of ambiguous multiple replacements.</li> <li>There may be a compelling use case for such a feature in the future, but generalization before the basic feature sees real-world use would be easy to get permanently wrong.</li> </ul> </section> <section id="alternative-method-names"> <h3><a class="toc-backref" href="#alternative-method-names" role="doc-backlink">Alternative Method Names</a></h3> Several alternatives method names have been proposed. Some are listed below, along with commentary for why they should be rejected in favor of <code class="docutils literal notranslate">removeprefix</code> (the same arguments hold for <code class="docutils literal notranslate">removesuffix</code>). <ul> <li><code class="docutils literal notranslate">ltrim</code>, <code class="docutils literal notranslate">trimprefix</code>, etc.:“Trim” does in other languages (e.g. JavaScript, Java, Go, PHP) what <code class="docutils literal notranslate">strip</code> methods do in Python. </li> <li><code class="docutils literal notranslate">lstrip(string=...)</code>This would avoid adding a new method, but for different behavior, it’s better to have two different methods than one method with a keyword argument that selects the behavior. </li> <li><code class="docutils literal notranslate">remove_prefix</code>:All of the other methods of the string API, e.g. <code class="docutils literal notranslate">str.startswith()</code>, use <code class="docutils literal notranslate">lowercase</code> rather than <code class="docutils literal notranslate">lower_case_with_underscores</code>. </li> <li><code class="docutils literal notranslate">removeleft</code>, <code class="docutils literal notranslate">leftremove</code>, or <code class="docutils literal notranslate">lremove</code>:The explicitness of “prefix” is preferred. </li> <li><code class="docutils literal notranslate">cutprefix</code>, <code class="docutils literal notranslate">deleteprefix</code>, <code class="docutils literal notranslate">withoutprefix</code>, <code class="docutils literal notranslate">dropprefix</code>, etc.:Many of these might have been acceptable, but “remove” is unambiguous and matches how one would describe the “remove the prefix” behavior in English. </li> <li><code class="docutils literal notranslate">stripprefix</code>:Users may benefit from remembering that “strip” means working with sets of characters, while other methods work with substrings, so re-using “strip” here should be avoided. </li> </ul> </section> </section> <section id="how-to-teach-this"> <h2><a class="toc-backref" href="#how-to-teach-this" role="doc-backlink">How to Teach This</a></h2> Among the uses for the <code class="docutils literal notranslate">partition()</code>, <code class="docutils literal notranslate">startswith()</code>, and <code class="docutils literal notranslate">split()</code> string methods or the <code class="docutils literal notranslate">enumerate()</code> or <code class="docutils literal notranslate">zip()</code> built-in functions, a common theme is that if a beginner finds themselves manually indexing or slicing a string, then they should consider whether there is a higher-level method that better communicates what the code should do rather than merely how the code should do it. The proposed <code class="docutils literal notranslate">removeprefix()</code> and <code class="docutils literal notranslate">removesuffix()</code> methods expand the high-level string “toolbox” and further allow for this sort of skepticism toward manual slicing. The main opportunity for user confusion will be the conflation of <code class="docutils literal notranslate">lstrip</code>/<code class="docutils literal notranslate">rstrip</code> with <code class="docutils literal notranslate">removeprefix</code>/<code class="docutils literal notranslate">removesuffix</code>. It may therefore be helpful to emphasize (as the documentation will) the following differences between the methods: <ul class="simple"> <li><code class="docutils literal notranslate">(l/r)strip</code>:<ul> <li>The argument is interpreted as a character set.</li> <li>The characters are repeatedly removed from the appropriate end of the string.</li> </ul> </li> <li><code class="docutils literal notranslate">remove(prefix/suffix)</code>:<ul> <li>The argument is interpreted as an unbroken substring.</li> <li>Only at most one copy of the prefix/suffix is removed.</li> </ul> </li> </ul> </section> <section id="reference-implementation"> <h2><a class="toc-backref" href="#reference-implementation" role="doc-backlink">Reference Implementation</a></h2> See the pull request on GitHub <a class="footnote-reference brackets" href="#pr" id="id9">[1]</a>. </section> <section id="history-of-major-revisions"> <h2><a class="toc-backref" href="#history-of-major-revisions" role="doc-backlink">History of Major revisions</a></h2> <ul class="simple"> <li>Version 3: Remove tuple behavior.</li> <li>Version 2: Changed name to <code class="docutils literal notranslate">removeprefix</code>/<code class="docutils literal notranslate">removesuffix</code>; added support for tuples as arguments</li> <li>Version 1: Initial draft with <code class="docutils literal notranslate">cutprefix</code>/<code class="docutils literal notranslate">cutsuffix</code></li> </ul> </section> <section id="references"> <h2><a class="toc-backref" href="#references" role="doc-backlink">References</a></h2> <aside class="footnote-list brackets"> <aside class="footnote brackets" id="pr" role="doc-footnote"> <dt class="label" id="pr">[<a href="#id9">1</a>]</dt> <dd>GitHub pull request with implementation (<a class="reference external" href="https://github.com/python/cpython/pull/18939">https://github.com/python/cpython/pull/18939</a>)</aside> <aside class="footnote brackets" id="pyid" role="doc-footnote"> <dt class="label" id="pyid">[2] (<a href='#id1'>1</a>, <a href='#id8'>2</a>) </dt> <dd>[Python-Ideas] “New explicit methods to trim strings” (<a class="reference external" href="https://mail.python.org/archives/list/python-ideas@python.org/thread/RJARZSUKCXRJIP42Z2YBBAEN5XA7KEC3/">https://mail.python.org/archives/list/python-ideas@python.org/thread/RJARZSUKCXRJIP42Z2YBBAEN5XA7KEC3/</a>)</aside> <aside class="footnote brackets" id="id10" role="doc-footnote"> <dt class="label" id="id10">[<a href="#id2">3</a>]</dt> <dd>“Re: [Python-ideas] adding a trim convenience function” (<a class="reference external" href="https://mail.python.org/archives/list/python-ideas@python.org/thread/SJ7CKPZSKB5RWT7H3YNXOJUQ7QLD2R3X/#C2W5T7RCFSHU5XI72HG53A6R3J3SN4MV">https://mail.python.org/archives/list/python-ideas@python.org/thread/SJ7CKPZSKB5RWT7H3YNXOJUQ7QLD2R3X/#C2W5T7RCFSHU5XI72HG53A6R3J3SN4MV</a>)</aside> <aside class="footnote brackets" id="id11" role="doc-footnote"> <dt class="label" id="id11">[<a href="#id3">4</a>]</dt> <dd>“Re: [Python-Dev] strip behavior provides inconsistent results with certain strings” (<a class="reference external" href="https://mail.python.org/archives/list/python-ideas@python.org/thread/XYFQMFPUV6FR2N5BGYWPBVMZ5BE5PJ6C/#XYFQMFPUV6FR2N5BGYWPBVMZ5BE5PJ6C">https://mail.python.org/archives/list/python-ideas@python.org/thread/XYFQMFPUV6FR2N5BGYWPBVMZ5BE5PJ6C/#XYFQMFPUV6FR2N5BGYWPBVMZ5BE5PJ6C</a>)</aside> <aside class="footnote brackets" id="id12" role="doc-footnote"> <dt class="label" id="id12">[<a href="#id4">5</a>]</dt> <dd>[Python-Dev] “correction of a bug” (<a class="reference external" href="https://mail.python.org/archives/list/python-dev@python.org/thread/AOZ7RFQTQLCZCTVNKESZI67PB3PSS72X/#AOZ7RFQTQLCZCTVNKESZI67PB3PSS72X">https://mail.python.org/archives/list/python-dev@python.org/thread/AOZ7RFQTQLCZCTVNKESZI67PB3PSS72X/#AOZ7RFQTQLCZCTVNKESZI67PB3PSS72X</a>)</aside> <aside class="footnote brackets" id="id13" role="doc-footnote"> <dt class="label" id="id13">[<a href="#id5">6</a>]</dt> <dd>[Python-Dev] “str.lstrip bug?” (<a class="reference external" href="https://mail.python.org/archives/list/python-dev@python.org/thread/OJDKRIESKGTQFNLX6KZSGKU57UXNZYAN/#CYZUFFJ2Q5ZZKMJIQBZVZR4NSLK5ZPIH">https://mail.python.org/archives/list/python-dev@python.org/thread/OJDKRIESKGTQFNLX6KZSGKU57UXNZYAN/#CYZUFFJ2Q5ZZKMJIQBZVZR4NSLK5ZPIH</a>)</aside> <aside class="footnote brackets" id="id14" role="doc-footnote"> <dt class="label" id="id14">[<a href="#id6">7</a>]</dt> <dd>[Python-Dev] “strip behavior provides inconsistent results with certain strings” (<a class="reference external" href="https://mail.python.org/archives/list/python-dev@python.org/thread/ZWRGCGANHGVDPP44VQKRIYOYX7LNVDVG/#ZWRGCGANHGVDPP44VQKRIYOYX7LNVDVG">https://mail.python.org/archives/list/python-dev@python.org/thread/ZWRGCGANHGVDPP44VQKRIYOYX7LNVDVG/#ZWRGCGANHGVDPP44VQKRIYOYX7LNVDVG</a>)</aside> <aside class="footnote brackets" id="confusion" role="doc-footnote"> <dt class="label" id="confusion">[<a href="#id7">8</a>]</dt> <dd>Comment listing Bug Tracker and StackOverflow issues (<a class="reference external" href="https://mail.python.org/archives/list/python-ideas@python.org/message/GRGAFIII3AX22K3N3KT7RB4DPBY3LPVG/">https://mail.python.org/archives/list/python-ideas@python.org/message/GRGAFIII3AX22K3N3KT7RB4DPBY3LPVG/</a>)</aside> </aside> </section> <section id="copyright"> <h2><a class="toc-backref" href="#copyright" role="doc-backlink">Copyright</a></h2> This document is placed in the public domain or under the CC0-1.0-Universal license, whichever is more permissive. </section> </section> <hr class="docutils" /> Source: <a class="reference external" href="https://github.com/python/peps/blob/main/peps/pep-0616.rst">https://github.com/python/peps/blob/main/peps/pep-0616.rst</a> Last modified: <a class="reference external" href="https://github.com/python/peps/commits/main/peps/pep-0616.rst">2025-02-01 08:55:40 GMT</a> </article> <nav id="pep-sidebar"> <h2>Contents</h2> <ul> <li><a class="reference internal" href="#abstract">Abstract</a></li> <li><a class="reference internal" href="#rationale">Rationale</a></li> <li><a class="reference internal" href="#specification">Specification</a></li> <li><a class="reference internal" href="#motivating-examples-from-the-python-standard-library">Motivating examples from the Python standard library</a><ul> <li><a class="reference internal" href="#find-recursionlimit-py">find_recursionlimit.py</a></li> <li><a class="reference internal" href="#deccheck-py">deccheck.py</a></li> <li><a class="reference internal" href="#cookiejar-py">cookiejar.py</a></li> <li><a class="reference internal" href="#test-i18n-py">test_i18n.py</a></li> </ul> </li> <li><a class="reference internal" href="#rejected-ideas">Rejected Ideas</a><ul> <li><a class="reference internal" href="#expand-the-lstrip-and-rstrip-apis">Expand the lstrip and rstrip APIs</a></li> <li><a class="reference internal" href="#remove-multiple-copies-of-a-prefix">Remove multiple copies of a prefix</a></li> <li><a class="reference internal" href="#raising-an-exception-when-not-found">Raising an exception when not found</a></li> <li><a class="reference internal" href="#accepting-a-tuple-of-affixes">Accepting a tuple of affixes</a></li> <li><a class="reference internal" href="#alternative-method-names">Alternative Method Names</a></li> </ul> </li> <li><a class="reference internal" href="#how-to-teach-this">How to Teach This</a></li> <li><a class="reference internal" href="#reference-implementation">Reference Implementation</a></li> <li><a class="reference internal" href="#history-of-major-revisions">History of Major revisions</a></li> <li><a class="reference internal" href="#references">References</a></li> <li><a class="reference internal" href="#copyright">Copyright</a></li> </ul> <a id="source" href="https://github.com/python/peps/blob/main/peps/pep-0616.rst">Page Source (GitHub)</a> </nav> </section> 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