⬆️ Bump attrs from 21.4.0 to 22.1.0 (#33)

Bumps [attrs](https://github.com/python-attrs/attrs) from 21.4.0 to
22.1.0.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/python-attrs/attrs/releases">attrs's
releases</a>.</em></p>
<blockquote>
<h2>22.1.0</h2>
<h1>Highlights</h1>
<p>The main features of this release are:</p>
<ul>
<li>The departure of Python 2.7 (enjoy your retirement!),</li>
<li>and the arrival of Python 3.11.</li>
</ul>
<p>We had loftier goals feature-wise, but didn't want to block others
embracing Python 3.11.</p>
<p>❤️ <strong>Huge</strong> thanks to my <a
href="https://github.com/sponsors/hynek">GitHub sponsors</a>, <a
href="https://tidelift.com/subscription/pkg/pypi-attrs">Tidelift
subscribers</a>, and <a href="https://ko-fi.com/the_hynek">Ko-fi
buyers</a>! ❤️</p>
<p>None of my projects would exist in their current form without
you!</p>
<h1>Full Changelog</h1>
<h2>Backwards-incompatible Changes</h2>
<ul>
<li>
<p>Python 2.7 is not supported anymore.</p>
<p>Dealing with Python 2.7 tooling has become too difficult for a
volunteer-run project.</p>
<p>We have supported Python 2 more than 2 years after it was officially
discontinued and feel that we have paid our dues. All version up to
21.4.0 from December 2021 remain fully functional, of course. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/936">#936</a></p>
</li>
<li>
<p>The deprecated <code>cmp</code> attribute of
<code>attrs.Attribute</code> has been removed. This does not affect the
<em>cmp</em> argument to <code>attr.s</code> that can be used as a
shortcut to set <em>eq</em> and <em>order</em> at the same time. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/939">#939</a></p>
</li>
</ul>
<h2>Changes</h2>
<ul>
<li>Instantiation of frozen slotted classes is now faster. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/898">#898</a></li>
<li>If an <code>eq</code> key is defined, it is also used before hashing
the attribute. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/909">#909</a></li>
<li>Added <code>attrs.validators.min_len()</code>. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/916">#916</a></li>
<li><code>attrs.validators.deep_iterable()</code>'s
<em>member_validator</em> argument now also accepts a list of validators
and wraps them in an <code>attrs.validators.and_()</code>. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/925">#925</a></li>
<li>Added missing type stub re-imports for <code>attrs.converters</code>
and <code>attrs.filters</code>. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/931">#931</a></li>
<li>Added missing stub for <code>attr(s).cmp_using()</code>. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/949">#949</a></li>
<li><code>attrs.validators._in()</code>'s <code>ValueError</code> is not
missing the attribute, expected options, and the value it got anymore.
<a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/951">#951</a></li>
<li>Python 3.11 is now officially supported. <a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/969">#969</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/python-attrs/attrs/blob/main/CHANGELOG.rst">attrs's
changelog</a>.</em></p>
<blockquote>
<h2>22.1.0 (2022-07-28)</h2>
<p>Backwards-incompatible Changes
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^</p>
<ul>
<li>
<p>Python 2.7 is not supported anymore.</p>
<p>Dealing with Python 2.7 tooling has become too difficult for a
volunteer-run project.</p>
<p>We have supported Python 2 more than 2 years after it was officially
discontinued and feel that we have paid our dues.
All version up to 21.4.0 from December 2021 remain fully functional, of
course.
<code>[#936](python-attrs/attrs#936)
&lt;https://github.com/python-attrs/attrs/issues/936&gt;</code>_</p>
</li>
<li>
<p>The deprecated <code>cmp</code> attribute of
<code>attrs.Attribute</code> has been removed.
This does not affect the <em>cmp</em> argument to <code>attr.s</code>
that can be used as a shortcut to set <em>eq</em> and <em>order</em> at
the same time.
<code>[#939](python-attrs/attrs#939)
&lt;https://github.com/python-attrs/attrs/issues/939&gt;</code>_</p>
</li>
</ul>
<p>Changes
^^^^^^^</p>
<ul>
<li>Instantiation of frozen slotted classes is now faster.
<code>[#898](python-attrs/attrs#898)
&lt;https://github.com/python-attrs/attrs/issues/898&gt;</code>_</li>
<li>If an <code>eq</code> key is defined, it is also used before hashing
the attribute.
<code>[#909](python-attrs/attrs#909)
&lt;https://github.com/python-attrs/attrs/issues/909&gt;</code>_</li>
<li>Added <code>attrs.validators.min_len()</code>.
<code>[#916](python-attrs/attrs#916)
&lt;https://github.com/python-attrs/attrs/issues/916&gt;</code>_</li>
<li><code>attrs.validators.deep_iterable()</code>'s
<em>member_validator</em> argument now also accepts a list of validators
and wraps them in an <code>attrs.validators.and_()</code>.
<code>[#925](python-attrs/attrs#925)
&lt;https://github.com/python-attrs/attrs/issues/925&gt;</code>_</li>
<li>Added missing type stub re-imports for <code>attrs.converters</code>
and <code>attrs.filters</code>.
<code>[#931](python-attrs/attrs#931)
&lt;https://github.com/python-attrs/attrs/issues/931&gt;</code>_</li>
<li>Added missing stub for <code>attr(s).cmp_using()</code>.
<code>[#949](python-attrs/attrs#949)
&lt;https://github.com/python-attrs/attrs/issues/949&gt;</code>_</li>
<li><code>attrs.validators._in()</code>'s <code>ValueError</code> is not
missing the attribute, expected options, and the value it got anymore.
<code>[#951](python-attrs/attrs#951)
&lt;https://github.com/python-attrs/attrs/issues/951&gt;</code>_</li>
<li>Python 3.11 is now officially supported.
<code>[#969](python-attrs/attrs#969)
&lt;https://github.com/python-attrs/attrs/issues/969&gt;</code>_</li>
</ul>
<hr />
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/python-attrs/attrs/commit/b3dfebe2e10b44437c4f97d788fb5220d790efd0"><code>b3dfebe</code></a>
Prepare 22.1.0</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/c89abcd6e6a826b00898f93e851c96b78c80891f"><code>c89abcd</code></a>
It totally is correct</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/9f118b7dd5328ee5abd7f3880971ab9554047c3a"><code>9f118b7</code></a>
Tune first steps</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/a3d7f20e54ba29d5ec73563c167d877351228cf2"><code>a3d7f20</code></a>
Polish contributing guide</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/899497f165b3c8291b66c9c3a01b64881b69cf39"><code>899497f</code></a>
Clarify (c) ownership</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/696fd786901a6b82b828dd71e3fd64bfae1014ca"><code>696fd78</code></a>
Hyphenate compound adjectives</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/65c06831c1eee4d9895511c7db5caffba9d93c0e"><code>65c0683</code></a>
Use NG APIs in glossary</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/5d84d9a5686e8210b1616447ac05021b6b211157"><code>5d84d9a</code></a>
Move mypy config to pyproject.toml</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/1590917bf7c49e35bb429d117650f660aa45e0e4"><code>1590917</code></a>
Update readme.rst (<a
href="https://github-redirect.dependabot.com/python-attrs/attrs/issues/986">#986</a>)</li>
<li><a
href="https://github.com/python-attrs/attrs/commit/a67c84f51e4e3df875961d287583abaef673eb48"><code>a67c84f</code></a>
Add more prominent callout about slots to API docs</li>
<li>Additional commits viewable in <a
href="https://github.com/python-attrs/attrs/compare/21.4.0...22.1.0">compare
view</a></li>
</ul>
</details>
<br />


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</details>

requirements.txt

@@ -10,7 +10,7 @@ alabaster==0.7.12
     #   sphinx
 asttokens==2.0.8
     # via stack-data
-attrs==21.4.0
+attrs==22.1.0
     # via
     #   -r requirements.in
     #   jsonschema