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<h1>Python Enhancement Proposals</h1>
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<section id="pep-content">
<h1 class="page-title">PEP 396 Module Version Numbers</h1>
<dl class="rfc2822 field-list simple">
<dt class="field-odd">Author<span class="colon">:</span></dt>
<dd class="field-odd">Barry Warsaw &lt;barry&#32;&#97;t&#32;python.org&gt;</dd>
<dt class="field-even">Status<span class="colon">:</span></dt>
<dd class="field-even"><abbr title="Removed from consideration by sponsor or authors">Withdrawn</abbr></dd>
<dt class="field-odd">Type<span class="colon">:</span></dt>
<dd class="field-odd"><abbr title="Non-normative PEP containing background, guidelines or other information relevant to the Python ecosystem">Informational</abbr></dd>
<dt class="field-even">Topic<span class="colon">:</span></dt>
<dd class="field-even"><a class="reference external" href="../topic/packaging/">Packaging</a></dd>
<dt class="field-odd">Created<span class="colon">:</span></dt>
<dd class="field-odd">16-Mar-2011</dd>
<dt class="field-even">Post-History<span class="colon">:</span></dt>
<dd class="field-even">05-Apr-2011</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="#pep-rejection-withdrawal">PEP Rejection/Withdrawal</a></li>
<li><a class="reference internal" href="#user-stories">User Stories</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="#examples">Examples</a></li>
<li><a class="reference internal" href="#deriving">Deriving</a><ul>
<li><a class="reference internal" href="#classic-distutils">Classic distutils</a></li>
<li><a class="reference internal" href="#distutils2">Distutils2</a></li>
</ul>
</li>
<li><a class="reference internal" href="#pep-376-metadata">PEP 376 metadata</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>
<div class="pep-banner sticky-banner deprecated withdrawn admonition important">
<p class="admonition-title">Important</p>
<p>This PEP has been withdrawn.</p>
<p class="close-button">×</p>
<p>Refer to <a class="reference external" href="https://packaging.python.org/en/latest/discussions/versioning/#runtime-version-access" title="(in Python Packaging User Guide)"><span>Accessing version information at runtime</span></a> and
<a class="reference external" href="https://packaging.python.org/en/latest/discussions/single-source-version/#single-source-version" title="(in Python Packaging User Guide)"><span>Single-sourcing the Project Version</span></a> in the Python
Packaging User Guide for up to date recommendations on
accessing package version information at runtime,
and on defining runtime <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attributes which are
automatically kept consistent with package distribution metadata</p>
<p></p>
</div>
<section id="abstract">
<h2><a class="toc-backref" href="#abstract" role="doc-backlink">Abstract</a></h2>
<p>Given that it is useful and common to specify version numbers for
Python modules, and given that different ways of doing this have grown
organically within the Python community, it is useful to establish
standard conventions for module authors to adhere to and reference.
This informational PEP describes best practices for Python module
authors who want to define the version number of their Python module.</p>
<p>Conformance with this PEP is optional, however other Python tools
(such as <code class="docutils literal notranslate"><span class="pre">distutils2</span></code> <a class="footnote-reference brackets" href="#id9" id="id1">[1]</a>) may be adapted to use the conventions
defined here.</p>
</section>
<section id="pep-rejection-withdrawal">
<h2><a class="toc-backref" href="#pep-rejection-withdrawal" role="doc-backlink">PEP Rejection/Withdrawal</a></h2>
<p>This PEP was formally rejected on 2021-04-14. The packaging ecosystem
has changed significantly in the intervening years since this PEP was
first written, and APIs such as <code class="docutils literal notranslate"><span class="pre">importlib.metadata.version()</span></code> <a class="footnote-reference brackets" href="#id15" id="id2">[11]</a>
provide for a much better experience.</p>
<p>This rejection was reclassified as a withdrawal on 2024-10-21,
as the previous state was being misinterpreted <a class="footnote-reference brackets" href="#id16" id="id3">[12]</a> as suggesting
that <em>no</em> modules should be defining <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attributes,
which definitely isnt the case.</p>
<p>Modules are still free to define <code class="docutils literal notranslate"><span class="pre">__version__</span></code> if they choose to.
However, choosing <em>not</em> to do so wont interfere with looking up
the version information for installed distribution packages, so an
Informational PEP isnt the right tool to document community
conventions around the use of module <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attributes
(theyre better covered as part of the Python Packaging User Guide).</p>
</section>
<section id="user-stories">
<h2><a class="toc-backref" href="#user-stories" role="doc-backlink">User Stories</a></h2>
<p>Alice is writing a new module, called <code class="docutils literal notranslate"><span class="pre">alice</span></code>, which she wants to
share with other Python developers. <code class="docutils literal notranslate"><span class="pre">alice</span></code> is a simple module and
lives in one file, <code class="docutils literal notranslate"><span class="pre">alice.py</span></code>. Alice wants to specify a version
number so that her users can tell which version they are using.
Because her module lives entirely in one file, she wants to add the
version number to that file.</p>
<p>Bob has written a module called <code class="docutils literal notranslate"><span class="pre">bob</span></code> which he has shared with many
users. <code class="docutils literal notranslate"><span class="pre">bob.py</span></code> contains a version number for the convenience of
his users. Bob learns about the Cheeseshop <a class="footnote-reference brackets" href="#id10" id="id4">[2]</a>, and adds some simple
packaging using classic distutils so that he can upload <em>The Bob
Bundle</em> to the Cheeseshop. Because <code class="docutils literal notranslate"><span class="pre">bob.py</span></code> already specifies a
version number which his users can access programmatically, he wants
the same API to continue to work even though his users now get it from
the Cheeseshop.</p>
<p>Carol maintains several namespace packages, each of which are
independently developed and distributed. In order for her users to
properly specify dependencies on the right versions of her packages,
she specifies the version numbers in the namespace packages
<code class="docutils literal notranslate"><span class="pre">setup.py</span></code> file. Because Carol wants to have to update one version
number per package, she specifies the version number in her module and
has the <code class="docutils literal notranslate"><span class="pre">setup.py</span></code> extract the module version number when she builds
the <em>sdist</em> archive.</p>
<p>David maintains a package in the standard library, and also produces
standalone versions for other versions of Python. The standard
library copy defines the version number in the module, and this same
version number is used for the standalone distributions as well.</p>
</section>
<section id="rationale">
<h2><a class="toc-backref" href="#rationale" role="doc-backlink">Rationale</a></h2>
<p>Python modules, both in the standard library and available from third
parties, have long included version numbers. There are established
de facto standards for describing version numbers, and many ad-hoc
ways have grown organically over the years. Often, version numbers
can be retrieved from a module programmatically, by importing the
module and inspecting an attribute. Classic Python distutils
<code class="docutils literal notranslate"><span class="pre">setup()</span></code> functions <a class="footnote-reference brackets" href="#id11" id="id5">[3]</a> describe a <code class="docutils literal notranslate"><span class="pre">version</span></code> argument where the
releases version number can be specified. <a class="pep reference internal" href="../pep-0008/" title="PEP 8 Style Guide for Python Code">PEP 8</a> describes the
use of a module attribute called <code class="docutils literal notranslate"><span class="pre">__version__</span></code> for recording
“Subversion, CVS, or RCS” version strings using keyword expansion. In
the PEP authors own email archives, the earliest example of the use
of an <code class="docutils literal notranslate"><span class="pre">__version__</span></code> module attribute by independent module
developers dates back to 1995.</p>
<p>Another example of version information is the sqlite3 <a class="footnote-reference brackets" href="#id12" id="id6">[5]</a> module
with its <code class="docutils literal notranslate"><span class="pre">sqlite_version_info</span></code>, <code class="docutils literal notranslate"><span class="pre">version</span></code>, and <code class="docutils literal notranslate"><span class="pre">version_info</span></code>
attributes. It may not be immediately obvious which attribute
contains a version number for the module, and which contains a version
number for the underlying SQLite3 library.</p>
<p>This informational PEP codifies established practice, and recommends
standard ways of describing module version numbers, along with some
use cases for when and when <em>not</em> to include them. Its adoption
by module authors is purely voluntary; packaging tools in the standard
library will provide optional support for the standards defined
herein, and other tools in the Python universe may comply as well.</p>
</section>
<section id="specification">
<h2><a class="toc-backref" href="#specification" role="doc-backlink">Specification</a></h2>
<ol class="arabic simple">
<li>In general, modules in the standard library SHOULD NOT have version
numbers. They implicitly carry the version number of the Python
release they are included in.</li>
<li>On a case-by-case basis, standard library modules which are also
released in standalone form for other Python versions MAY include a
module version number when included in the standard library, and
SHOULD include a version number when packaged separately.</li>
<li>When a module (or package) includes a version number, the version
SHOULD be available in the <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attribute.</li>
<li>For modules which live inside a namespace package, the module
SHOULD include the <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attribute. The namespace
package itself SHOULD NOT include its own <code class="docutils literal notranslate"><span class="pre">__version__</span></code>
attribute.</li>
<li>The <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attributes value SHOULD be a string.</li>
<li>Module version numbers SHOULD conform to the normalized version
format specified in <a class="pep reference internal" href="../pep-0386/" title="PEP 386 Changing the version comparison module in Distutils">PEP 386</a>.</li>
<li>Module version numbers SHOULD NOT contain version control system
supplied revision numbers, or any other semantically different
version numbers (e.g. underlying library version number).</li>
<li>The <code class="docutils literal notranslate"><span class="pre">version</span></code> attribute in a classic distutils <code class="docutils literal notranslate"><span class="pre">setup.py</span></code>
file, or the <a class="pep reference internal" href="../pep-0345/" title="PEP 345 Metadata for Python Software Packages 1.2">PEP 345</a> <code class="docutils literal notranslate"><span class="pre">Version</span></code> metadata field SHOULD be
derived from the <code class="docutils literal notranslate"><span class="pre">__version__</span></code> field, or vice versa.</li>
</ol>
</section>
<section id="examples">
<h2><a class="toc-backref" href="#examples" role="doc-backlink">Examples</a></h2>
<p>Retrieving the version number from a third party package:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">bzrlib</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">bzrlib</span><span class="o">.</span><span class="n">__version__</span>
<span class="go">&#39;2.3.0&#39;</span>
</pre></div>
</div>
<p>Retrieving the version number from a standard library package that is
also distributed as a standalone module:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">email</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">email</span><span class="o">.</span><span class="n">__version__</span>
<span class="go">&#39;5.1.0&#39;</span>
</pre></div>
</div>
<p>Version numbers for namespace packages:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">flufl.i18n</span>
<span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">flufl.enum</span>
<span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">flufl.lock</span>
<span class="gp">&gt;&gt;&gt; </span><span class="nb">print</span> <span class="n">flufl</span><span class="o">.</span><span class="n">i18n</span><span class="o">.</span><span class="n">__version__</span>
<span class="go">1.0.4</span>
<span class="gp">&gt;&gt;&gt; </span><span class="nb">print</span> <span class="n">flufl</span><span class="o">.</span><span class="n">enum</span><span class="o">.</span><span class="n">__version__</span>
<span class="go">3.1</span>
<span class="gp">&gt;&gt;&gt; </span><span class="nb">print</span> <span class="n">flufl</span><span class="o">.</span><span class="n">lock</span><span class="o">.</span><span class="n">__version__</span>
<span class="go">2.1</span>
<span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">flufl</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">flufl</span><span class="o">.</span><span class="n">__version__</span>
<span class="gt">Traceback (most recent call last):</span>
File <span class="nb">&quot;&lt;stdin&gt;&quot;</span>, line <span class="m">1</span>, in <span class="n">&lt;module&gt;</span>
<span class="gr">AttributeError</span>: <span class="n">&#39;module&#39; object has no attribute &#39;__version__&#39;</span>
<span class="gp">&gt;&gt;&gt;</span>
</pre></div>
</div>
</section>
<section id="deriving">
<h2><a class="toc-backref" href="#deriving" role="doc-backlink">Deriving</a></h2>
<p>Module version numbers can appear in at least two places, and
sometimes more. For example, in accordance with this PEP, they are
available programmatically on the modules <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attribute.
In a classic distutils <code class="docutils literal notranslate"><span class="pre">setup.py</span></code> file, the <code class="docutils literal notranslate"><span class="pre">setup()</span></code> function
takes a <code class="docutils literal notranslate"><span class="pre">version</span></code> argument, while the distutils2 <code class="docutils literal notranslate"><span class="pre">setup.cfg</span></code> file
has a <code class="docutils literal notranslate"><span class="pre">version</span></code> key. The version number must also get into the PEP
345 metadata, preferably when the <em>sdist</em> archive is built. Its
desirable for module authors to only have to specify the version
number once, and have all the other uses derive from this single
definition.</p>
<p>This could be done in any number of ways, a few of which are outlined
below. These are included for illustrative purposes only and are not
intended to be definitive, complete, or all-encompassing. Other
approaches are possible, and some included below may have limitations
that prevent their use in some situations.</p>
<p>Lets say Elle adds this attribute to her module file <code class="docutils literal notranslate"><span class="pre">elle.py</span></code>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="n">__version__</span> <span class="o">=</span> <span class="s1">&#39;3.1.1&#39;</span>
</pre></div>
</div>
<section id="classic-distutils">
<h3><a class="toc-backref" href="#classic-distutils" role="doc-backlink">Classic distutils</a></h3>
<p>In classic distutils, the simplest way to add the version string to
the <code class="docutils literal notranslate"><span class="pre">setup()</span></code> function in <code class="docutils literal notranslate"><span class="pre">setup.py</span></code> is to do something like
this:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">elle</span> <span class="kn">import</span> <span class="n">__version__</span>
<span class="n">setup</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;elle&#39;</span><span class="p">,</span> <span class="n">version</span><span class="o">=</span><span class="n">__version__</span><span class="p">)</span>
</pre></div>
</div>
<p>In the PEP authors experience however, this can fail in some cases,
such as when the module uses automatic Python 3 conversion via the
<code class="docutils literal notranslate"><span class="pre">2to3</span></code> program (because <code class="docutils literal notranslate"><span class="pre">setup.py</span></code> is executed by Python 3 before
the <code class="docutils literal notranslate"><span class="pre">elle</span></code> module has been converted).</p>
<p>In that case, its not much more difficult to write a little code to
parse the <code class="docutils literal notranslate"><span class="pre">__version__</span></code> from the file rather than importing it.
Without providing too much detail, its likely that modules such as
<code class="docutils literal notranslate"><span class="pre">distutils2</span></code> will provide a way to parse version strings from files.
E.g.:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">distutils2</span> <span class="kn">import</span> <span class="n">get_version</span>
<span class="n">setup</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;elle&#39;</span><span class="p">,</span> <span class="n">version</span><span class="o">=</span><span class="n">get_version</span><span class="p">(</span><span class="s1">&#39;elle.py&#39;</span><span class="p">))</span>
</pre></div>
</div>
</section>
<section id="distutils2">
<h3><a class="toc-backref" href="#distutils2" role="doc-backlink">Distutils2</a></h3>
<p>Because the distutils2 style <code class="docutils literal notranslate"><span class="pre">setup.cfg</span></code> is declarative, we cant
run any code to extract the <code class="docutils literal notranslate"><span class="pre">__version__</span></code> attribute, either via
import or via parsing.</p>
<p>In consultation with the distutils-sig <a class="footnote-reference brackets" href="#id14" id="id7">[9]</a>, two options are
proposed. Both entail containing the version number in a file, and
declaring that file in the <code class="docutils literal notranslate"><span class="pre">setup.cfg</span></code>. When the entire contents of
the file contains the version number, the <code class="docutils literal notranslate"><span class="pre">version-file</span></code> key will be
used:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="p">[</span><span class="n">metadata</span><span class="p">]</span>
<span class="n">version</span><span class="o">-</span><span class="n">file</span><span class="p">:</span> <span class="n">version</span><span class="o">.</span><span class="n">txt</span>
</pre></div>
</div>
<p>When the version number is contained within a larger file, e.g. of
Python code, such that the file must be parsed to extract the version,
the key <code class="docutils literal notranslate"><span class="pre">version-from-file</span></code> will be used:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="p">[</span><span class="n">metadata</span><span class="p">]</span>
<span class="n">version</span><span class="o">-</span><span class="n">from</span><span class="o">-</span><span class="n">file</span><span class="p">:</span> <span class="n">elle</span><span class="o">.</span><span class="n">py</span>
</pre></div>
</div>
<p>A parsing method similar to that described above will be performed on
the file named after the colon. The exact recipe for doing this will
be discussed in the appropriate distutils2 development forum.</p>
<p>An alternative is to only define the version number in <code class="docutils literal notranslate"><span class="pre">setup.cfg</span></code>
and use the <code class="docutils literal notranslate"><span class="pre">pkgutil</span></code> module <a class="footnote-reference brackets" href="#id13" id="id8">[8]</a> to make it available
programmatically. E.g. in <code class="docutils literal notranslate"><span class="pre">elle.py</span></code>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">distutils2._backport</span> <span class="kn">import</span> <span class="n">pkgutil</span>
<span class="n">__version__</span> <span class="o">=</span> <span class="n">pkgutil</span><span class="o">.</span><span class="n">get_distribution</span><span class="p">(</span><span class="s1">&#39;elle&#39;</span><span class="p">)</span><span class="o">.</span><span class="n">metadata</span><span class="p">[</span><span class="s1">&#39;version&#39;</span><span class="p">]</span>
</pre></div>
</div>
</section>
</section>
<section id="pep-376-metadata">
<h2><a class="toc-backref" href="#pep-376-metadata" role="doc-backlink">PEP 376 metadata</a></h2>
<p><a class="pep reference internal" href="../pep-0376/" title="PEP 376 Database of Installed Python Distributions">PEP 376</a> defines a standard for static metadata, but doesnt
describe the process by which this metadata gets created. It is
highly desirable for the derived version information to be placed into
the <a class="pep reference internal" href="../pep-0376/" title="PEP 376 Database of Installed Python Distributions">PEP 376</a> <code class="docutils literal notranslate"><span class="pre">.dist-info</span></code> metadata at build-time rather than
install-time. This way, the metadata will be available for
introspection even when the code is not installed.</p>
</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="id9" role="doc-footnote">
<dt class="label" id="id9">[<a href="#id1">1</a>]</dt>
<dd>Distutils2 documentation
(<a class="reference external" href="http://distutils2.notmyidea.org/">http://distutils2.notmyidea.org/</a>)</aside>
<aside class="footnote brackets" id="id10" role="doc-footnote">
<dt class="label" id="id10">[<a href="#id4">2</a>]</dt>
<dd>The Cheeseshop (Python Package Index)
(<a class="reference external" href="http://pypi.python.org">http://pypi.python.org</a>)</aside>
<aside class="footnote brackets" id="id11" role="doc-footnote">
<dt class="label" id="id11">[<a href="#id5">3</a>]</dt>
<dd><a class="reference external" href="http://docs.python.org/distutils/setupscript.html">http://docs.python.org/distutils/setupscript.html</a></aside>
<aside class="footnote brackets" id="id12" role="doc-footnote">
<dt class="label" id="id12">[<a href="#id6">5</a>]</dt>
<dd>sqlite3 module documentation
(<a class="reference external" href="http://docs.python.org/library/sqlite3.html">http://docs.python.org/library/sqlite3.html</a>)</aside>
<aside class="footnote brackets" id="id13" role="doc-footnote">
<dt class="label" id="id13">[<a href="#id8">8</a>]</dt>
<dd>pkgutil - Package utilities
(<a class="reference external" href="http://distutils2.notmyidea.org/library/pkgutil.html">http://distutils2.notmyidea.org/library/pkgutil.html</a>)</aside>
<aside class="footnote brackets" id="id14" role="doc-footnote">
<dt class="label" id="id14">[<a href="#id7">9</a>]</dt>
<dd><a class="reference external" href="https://mail.python.org/pipermail/distutils-sig/2011-June/017862.html">https://mail.python.org/pipermail/distutils-sig/2011-June/017862.html</a></aside>
<aside class="footnote brackets" id="id15" role="doc-footnote">
<dt class="label" id="id15">[<a href="#id2">11</a>]</dt>
<dd>importlib.metadata
(<a class="reference external" href="https://docs.python.org/3/library/importlib.metadata.html#distribution-versions">https://docs.python.org/3/library/importlib.metadata.html#distribution-versions</a>)</aside>
<aside class="footnote brackets" id="id16" role="doc-footnote">
<dt class="label" id="id16">[<a href="#id3">12</a>]</dt>
<dd>Misinterpreting the significance of this PEPs rejection
(<a class="reference external" href="https://discuss.python.org/t/please-make-package-version-go-away/58501">https://discuss.python.org/t/please-make-package-version-go-away/58501</a>)</aside>
</aside>
</section>
<section id="copyright">
<h2><a class="toc-backref" href="#copyright" role="doc-backlink">Copyright</a></h2>
<p>This document has been placed in the public domain.</p>
</section>
</section>
<hr class="docutils" />
<p>Source: <a class="reference external" href="https://github.com/python/peps/blob/main/peps/pep-0396.rst">https://github.com/python/peps/blob/main/peps/pep-0396.rst</a></p>
<p>Last modified: <a class="reference external" href="https://github.com/python/peps/commits/main/peps/pep-0396.rst">2024-10-23 14:52:37 GMT</a></p>
</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="#pep-rejection-withdrawal">PEP Rejection/Withdrawal</a></li>
<li><a class="reference internal" href="#user-stories">User Stories</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="#examples">Examples</a></li>
<li><a class="reference internal" href="#deriving">Deriving</a><ul>
<li><a class="reference internal" href="#classic-distutils">Classic distutils</a></li>
<li><a class="reference internal" href="#distutils2">Distutils2</a></li>
</ul>
</li>
<li><a class="reference internal" href="#pep-376-metadata">PEP 376 metadata</a></li>
<li><a class="reference internal" href="#references">References</a></li>
<li><a class="reference internal" href="#copyright">Copyright</a></li>
</ul>
<br>
<a id="source" href="https://github.com/python/peps/blob/main/peps/pep-0396.rst">Page Source (GitHub)</a>
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