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<section id="pep-content">
<h1 class="page-title">PEP 404 – Python 2.8 Un-release Schedule</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abbr title="Accepted and implementation complete, or no longer active">Final</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/release/">Release</a></dd>
<dt class="field-odd">Created<span class="colon">:</span></dt>
<dd class="field-odd">09-Nov-2011</dd>
<dt class="field-even">Python-Version<span class="colon">:</span></dt>
<dd class="field-even">2.8</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="#un-release-manager-and-crew">Un-release Manager and Crew</a></li>
<li><a class="reference internal" href="#un-release-schedule">Un-release Schedule</a></li>
<li><a class="reference internal" href="#official-pronouncement">Official pronouncement</a></li>
<li><a class="reference internal" href="#upgrade-path">Upgrade path</a></li>
<li><a class="reference internal" href="#and-now-for-something-completely-different">And Now For Something Completely Different</a><ul>
<li><a class="reference internal" href="#strings-and-bytes">Strings and bytes</a></li>
<li><a class="reference internal" href="#numbers">Numbers</a></li>
<li><a class="reference internal" href="#classes">Classes</a></li>
<li><a class="reference internal" href="#multiple-spellings">Multiple spellings</a></li>
<li><a class="reference internal" href="#imports">Imports</a></li>
<li><a class="reference internal" href="#iterators-and-views">Iterators and views</a></li>
</ul>
</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>
<p>This document describes the un-development and un-release schedule for Python
2.8.</p>
</section>
<section id="un-release-manager-and-crew">
<h2><a class="toc-backref" href="#un-release-manager-and-crew" role="doc-backlink">Un-release Manager and Crew</a></h2>
<table class="docutils align-default">
<thead>
<tr class="row-odd"><th class="head">Position</th>
<th class="head">Name</th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td>2.8 Un-release Manager</td>
<td>Cardinal Biggles</td>
</tr>
</tbody>
</table>
</section>
<section id="un-release-schedule">
<h2><a class="toc-backref" href="#un-release-schedule" role="doc-backlink">Un-release Schedule</a></h2>
<p>The current un-schedule is:</p>
<ul class="simple">
<li>2.8 final Never</li>
</ul>
</section>
<section id="official-pronouncement">
<h2><a class="toc-backref" href="#official-pronouncement" role="doc-backlink">Official pronouncement</a></h2>
<p>Rule number six: there is <em>no</em> official Python 2.8 release. There never will
be an official Python 2.8 release. It is an ex-release. Python 2.7
is the end of the Python 2 line of development.</p>
</section>
<section id="upgrade-path">
<h2><a class="toc-backref" href="#upgrade-path" role="doc-backlink">Upgrade path</a></h2>
<p>The official upgrade path from Python 2.7 is to Python 3.</p>
</section>
<section id="and-now-for-something-completely-different">
<h2><a class="toc-backref" href="#and-now-for-something-completely-different" role="doc-backlink">And Now For Something Completely Different</a></h2>
<p>In all seriousness, there are important reasons why there won’t be an
official Python 2.8 release, and why you should plan to migrate
instead to Python 3.</p>
<p>Python is (as of this writing) more than 20 years old, and Guido and the
community have learned a lot in those intervening years. Guido’s
original concept for Python 3 was to make changes to the language
primarily to remove the warts that had grown in the preceding
versions. Python 3 was not to be a complete redesign, but instead an
evolution of the language, and while maintaining full backward
compatibility with Python 2 was explicitly off-the-table, neither were
gratuitous changes in syntax or semantics acceptable. In most cases,
Python 2 code can be translated fairly easily to Python 3, sometimes
entirely mechanically by such tools as <a class="reference external" href="http://docs.python.org/library/2to3.html">2to3</a> (there’s also a non-trivial
subset of the language that will run without modification on both 2.7 and
3.x).</p>
<p>Because maintaining multiple versions of Python is a significant drag
on the resources of the Python developers, and because the
improvements to the language and libraries embodied in Python 3 are so
important, it was decided to end the Python 2 lineage with Python
2.7. Thus, all new development occurs in the Python 3 line of
development, and there will never be an official Python 2.8 release.
Python 2.7 will however be maintained for longer than the usual period
of time.</p>
<p>Here are some highlights of the significant improvements in Python 3.
You can read in more detail on the <a class="reference external" href="http://docs.python.org/release/3.0.1/whatsnew/3.0.html">differences</a> between Python 2 and
Python 3. There are also many good guides on <a class="reference external" href="http://python3porting.com/">porting</a> from Python 2
to Python 3.</p>
<section id="strings-and-bytes">
<h3><a class="toc-backref" href="#strings-and-bytes" role="doc-backlink">Strings and bytes</a></h3>
<p>Python 2’s basic original strings are called 8-bit strings, and
they play a dual role in Python 2 as both ASCII text and as byte
sequences. While Python 2 also has a unicode string type, the
fundamental ambiguity of the core string type, coupled with Python 2’s
default behavior of supporting automatic coercion from 8-bit strings
to unicode objects when the two are combined, often leads to
<code class="docutils literal notranslate"><span class="pre">UnicodeError</span></code>s. Python 3’s standard string type is Unicode based, and
Python 3 adds a dedicated bytes type, but critically, no automatic coercion
between bytes and unicode strings is provided. The closest the language gets
to implicit coercion are a few text-based APIs that assume a default
encoding (usually UTF-8) if no encoding is explicitly stated. Thus, the core
interpreter, its I/O libraries, module names, etc. are clear in their
distinction between unicode strings and bytes. Python 3’s unicode
support even extends to the filesystem, so that non-ASCII file names are
natively supported.</p>
<p>This string/bytes clarity is often a source of difficulty in
transitioning existing code to Python 3, because many third party
libraries and applications are themselves ambiguous in this
distinction. Once migrated though, most <code class="docutils literal notranslate"><span class="pre">UnicodeError</span></code>s can be
eliminated.</p>
</section>
<section id="numbers">
<h3><a class="toc-backref" href="#numbers" role="doc-backlink">Numbers</a></h3>
<p>Python 2 has two basic integer types, a native machine-sized <code class="docutils literal notranslate"><span class="pre">int</span></code>
type, and an arbitrary length <code class="docutils literal notranslate"><span class="pre">long</span></code> type. These have been merged in
Python 3 into a single <code class="docutils literal notranslate"><span class="pre">int</span></code> type analogous to Python 2’s <code class="docutils literal notranslate"><span class="pre">long</span></code>
type.</p>
<p>In addition, integer division now produces floating point numbers for
non-integer results.</p>
</section>
<section id="classes">
<h3><a class="toc-backref" href="#classes" role="doc-backlink">Classes</a></h3>
<p>Python 2 has two core class hierarchies, often called <em>classic
classes</em> and <em>new-style classes</em>. The latter allow for such things as
inheriting from the builtin basic types, support descriptor based tools
like the <code class="docutils literal notranslate"><span class="pre">property</span></code> builtin and provide a generally more sane and coherent
system for dealing with multiple inheritance. Python 3 provided the
opportunity to completely drop support for classic classes, so all classes
in Python 3 automatically use the new-style semantics (although that’s a
misnomer now). There is no need to explicitly inherit from <code class="docutils literal notranslate"><span class="pre">object</span></code> or set
the default metatype to enable them (in fact, setting a default metatype at
the module level is no longer supported - the default metatype is always
<code class="docutils literal notranslate"><span class="pre">object</span></code>).</p>
<p>The mechanism for explicitly specifying a metaclass has also changed to use
a <code class="docutils literal notranslate"><span class="pre">metaclass</span></code> keyword argument in the class header line rather than a
<code class="docutils literal notranslate"><span class="pre">__metaclass__</span></code> magic attribute in the class body.</p>
</section>
<section id="multiple-spellings">
<h3><a class="toc-backref" href="#multiple-spellings" role="doc-backlink">Multiple spellings</a></h3>
<p>There are many cases in Python 2 where multiple spellings of some
constructs exist, such as <code class="docutils literal notranslate"><span class="pre">repr()</span></code> and <em>backticks</em>, or the two
inequality operators <code class="docutils literal notranslate"><span class="pre">!=</span></code> and <code class="docutils literal notranslate"><span class="pre">&lt;&gt;</span></code>. In all cases, Python 3 has chosen
exactly one spelling and removed the other (e.g. <code class="docutils literal notranslate"><span class="pre">repr()</span></code> and <code class="docutils literal notranslate"><span class="pre">!=</span></code>
were kept).</p>
</section>
<section id="imports">
<h3><a class="toc-backref" href="#imports" role="doc-backlink">Imports</a></h3>
<p>In Python 3, implicit relative imports within packages are no longer
available - only absolute imports and explicit relative imports are
supported. In addition, star imports (e.g. <code class="docutils literal notranslate"><span class="pre">from</span> <span class="pre">x</span> <span class="pre">import</span> <span class="pre">*</span></code>) are only
permitted in module level code.</p>
<p>Also, some areas of the standard library have been reorganized to make
the naming scheme more intuitive. Some rarely used builtins have been
relocated to standard library modules.</p>
</section>
<section id="iterators-and-views">
<h3><a class="toc-backref" href="#iterators-and-views" role="doc-backlink">Iterators and views</a></h3>
<p>Many APIs, which in Python 2 returned concrete lists, in Python 3 now
return iterators or lightweight <em>views</em>.</p>
</section>
</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-0404.rst">https://github.com/python/peps/blob/main/peps/pep-0404.rst</a></p>
<p>Last modified: <a class="reference external" href="https://github.com/python/peps/commits/main/peps/pep-0404.rst">2023-09-09 17:39:29 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="#un-release-manager-and-crew">Un-release Manager and Crew</a></li>
<li><a class="reference internal" href="#un-release-schedule">Un-release Schedule</a></li>
<li><a class="reference internal" href="#official-pronouncement">Official pronouncement</a></li>
<li><a class="reference internal" href="#upgrade-path">Upgrade path</a></li>
<li><a class="reference internal" href="#and-now-for-something-completely-different">And Now For Something Completely Different</a><ul>
<li><a class="reference internal" href="#strings-and-bytes">Strings and bytes</a></li>
<li><a class="reference internal" href="#numbers">Numbers</a></li>
<li><a class="reference internal" href="#classes">Classes</a></li>
<li><a class="reference internal" href="#multiple-spellings">Multiple spellings</a></li>
<li><a class="reference internal" href="#imports">Imports</a></li>
<li><a class="reference internal" href="#iterators-and-views">Iterators and views</a></li>
</ul>
</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-0404.rst">Page Source (GitHub)</a>
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