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<span id="development"></span><h1>Development Tools<a class="headerlink" href="#development-tools" title="Permalink to this headline">¶</a></h1>
<p>The modules described in this chapter help you write software. For example, the
<a class="reference internal" href="pydoc.html#module-pydoc" title="pydoc: Documentation generator and online help system."><code class="xref py py-mod docutils literal notranslate"><span class="pre">pydoc</span></code></a> module takes a module and generates documentation based on the
module’s contents. The <a class="reference internal" href="doctest.html#module-doctest" title="doctest: Test pieces of code within docstrings."><code class="xref py py-mod docutils literal notranslate"><span class="pre">doctest</span></code></a> and <a class="reference internal" href="unittest.html#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> modules contains
frameworks for writing unit tests that automatically exercise code and verify
that the expected output is produced. <strong class="program">2to3</strong> can translate Python 2.x
source code into valid Python 3.x code.</p>
<p>The list of modules described in this chapter is:</p>
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<li class="toctree-l1"><a class="reference internal" href="typing.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">typing</span></code> — Support for type hints</a><ul>
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<li class="toctree-l2"><a class="reference internal" href="typing.html#user-defined-generic-types">User-defined generic types</a></li>
<li class="toctree-l2"><a class="reference internal" href="typing.html#the-any-type">The <code class="xref py py-data docutils literal notranslate"><span class="pre">Any</span></code> type</a></li>
<li class="toctree-l2"><a class="reference internal" href="typing.html#classes-functions-and-decorators">Classes, functions, and decorators</a></li>
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<li class="toctree-l1"><a class="reference internal" href="pydoc.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pydoc</span></code> — Documentation generator and online help system</a></li>
<li class="toctree-l1"><a class="reference internal" href="doctest.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">doctest</span></code> — Test interactive Python examples</a><ul>
<li class="toctree-l2"><a class="reference internal" href="doctest.html#simple-usage-checking-examples-in-docstrings">Simple Usage: Checking Examples in Docstrings</a></li>
<li class="toctree-l2"><a class="reference internal" href="doctest.html#simple-usage-checking-examples-in-a-text-file">Simple Usage: Checking Examples in a Text File</a></li>
<li class="toctree-l2"><a class="reference internal" href="doctest.html#how-it-works">How It Works</a><ul>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#which-docstrings-are-examined">Which Docstrings Are Examined?</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#how-are-docstring-examples-recognized">How are Docstring Examples Recognized?</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#what-s-the-execution-context">What’s the Execution Context?</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#what-about-exceptions">What About Exceptions?</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#option-flags">Option Flags</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#directives">Directives</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#warnings">Warnings</a></li>
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<li class="toctree-l2"><a class="reference internal" href="doctest.html#basic-api">Basic API</a></li>
<li class="toctree-l2"><a class="reference internal" href="doctest.html#unittest-api">Unittest API</a></li>
<li class="toctree-l2"><a class="reference internal" href="doctest.html#advanced-api">Advanced API</a><ul>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#doctest-objects">DocTest Objects</a></li>
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<li class="toctree-l3"><a class="reference internal" href="doctest.html#doctestfinder-objects">DocTestFinder objects</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#doctestparser-objects">DocTestParser objects</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#doctestrunner-objects">DocTestRunner objects</a></li>
<li class="toctree-l3"><a class="reference internal" href="doctest.html#outputchecker-objects">OutputChecker objects</a></li>
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<li class="toctree-l2"><a class="reference internal" href="doctest.html#debugging">Debugging</a></li>
<li class="toctree-l2"><a class="reference internal" href="doctest.html#soapbox">Soapbox</a></li>
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<li class="toctree-l1"><a class="reference internal" href="unittest.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code> — Unit testing framework</a><ul>
<li class="toctree-l2"><a class="reference internal" href="unittest.html#basic-example">Basic example</a></li>
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<li class="toctree-l2"><a class="reference internal" href="unittest.html#distinguishing-test-iterations-using-subtests">Distinguishing test iterations using subtests</a></li>
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<li class="toctree-l1"><a class="reference internal" href="unittest.mock.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest.mock</span></code> — mock object library</a><ul>
<li class="toctree-l2"><a class="reference internal" href="unittest.mock.html#quick-guide">Quick Guide</a></li>
<li class="toctree-l2"><a class="reference internal" href="unittest.mock.html#the-mock-class">The Mock Class</a><ul>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock.html#calling">Calling</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock.html#deleting-attributes">Deleting Attributes</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock.html#mock-names-and-the-name-attribute">Mock names and the name attribute</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock.html#attaching-mocks-as-attributes">Attaching Mocks as Attributes</a></li>
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<li class="toctree-l2"><a class="reference internal" href="unittest.mock.html#the-patchers">The patchers</a><ul>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock.html#patch">patch</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock.html#patch-object">patch.object</a></li>
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<li class="toctree-l2"><a class="reference internal" href="unittest.mock.html#magicmock-and-magic-method-support">MagicMock and magic method support</a><ul>
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<li class="toctree-l1"><a class="reference internal" href="unittest.mock-examples.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest.mock</span></code> — getting started</a><ul>
<li class="toctree-l2"><a class="reference internal" href="unittest.mock-examples.html#using-mock">Using Mock</a><ul>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mock-patching-methods">Mock Patching Methods</a></li>
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<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mocking-classes">Mocking Classes</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#naming-your-mocks">Naming your mocks</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#tracking-all-calls">Tracking all Calls</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#setting-return-values-and-attributes">Setting Return Values and Attributes</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#raising-exceptions-with-mocks">Raising exceptions with mocks</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#side-effect-functions-and-iterables">Side effect functions and iterables</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#creating-a-mock-from-an-existing-object">Creating a Mock from an Existing Object</a></li>
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<li class="toctree-l2"><a class="reference internal" href="unittest.mock-examples.html#patch-decorators">Patch Decorators</a></li>
<li class="toctree-l2"><a class="reference internal" href="unittest.mock-examples.html#further-examples">Further Examples</a><ul>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mocking-chained-calls">Mocking chained calls</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#partial-mocking">Partial mocking</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mocking-a-generator-method">Mocking a Generator Method</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#applying-the-same-patch-to-every-test-method">Applying the same patch to every test method</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mocking-unbound-methods">Mocking Unbound Methods</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#checking-multiple-calls-with-mock">Checking multiple calls with mock</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#coping-with-mutable-arguments">Coping with mutable arguments</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#nesting-patches">Nesting Patches</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mocking-a-dictionary-with-magicmock">Mocking a dictionary with MagicMock</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mock-subclasses-and-their-attributes">Mock subclasses and their attributes</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#mocking-imports-with-patch-dict">Mocking imports with patch.dict</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#tracking-order-of-calls-and-less-verbose-call-assertions">Tracking order of calls and less verbose call assertions</a></li>
<li class="toctree-l3"><a class="reference internal" href="unittest.mock-examples.html#more-complex-argument-matching">More complex argument matching</a></li>
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<li class="toctree-l1"><a class="reference internal" href="2to3.html">2to3 - Automated Python 2 to 3 code translation</a><ul>
<li class="toctree-l2"><a class="reference internal" href="2to3.html#using-2to3">Using 2to3</a></li>
<li class="toctree-l2"><a class="reference internal" href="2to3.html#fixers">Fixers</a></li>
<li class="toctree-l2"><a class="reference internal" href="2to3.html#module-lib2to3"><code class="xref py py-mod docutils literal notranslate"><span class="pre">lib2to3</span></code> - 2to3’s library</a></li>
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<li class="toctree-l1"><a class="reference internal" href="test.html"><code class="xref py py-mod docutils literal notranslate"><span class="pre">test</span></code> — Regression tests package for Python</a><ul>
<li class="toctree-l2"><a class="reference internal" href="test.html#writing-unit-tests-for-the-test-package">Writing Unit Tests for the <code class="xref py py-mod docutils literal notranslate"><span class="pre">test</span></code> package</a></li>
<li class="toctree-l2"><a class="reference internal" href="test.html#running-tests-using-the-command-line-interface">Running tests using the command-line interface</a></li>
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<li class="toctree-l1"><a class="reference internal" href="test.html#module-test.support"><code class="xref py py-mod docutils literal notranslate"><span class="pre">test.support</span></code> — Utilities for the Python test suite</a></li>
<li class="toctree-l1"><a class="reference internal" href="test.html#module-test.support.script_helper"><code class="xref py py-mod docutils literal notranslate"><span class="pre">test.support.script_helper</span></code> — Utilities for the Python execution tests</a></li>
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<p>See also the Python development mode: the <a class="reference internal" href="../using/cmdline.html#id5"><code class="xref std std-option docutils literal notranslate"><span class="pre">-X</span></code></a> <code class="docutils literal notranslate"><span class="pre">dev</span></code> option and
<span class="target" id="index-0"></span><a class="reference internal" href="../using/cmdline.html#envvar-PYTHONDEVMODE"><code class="xref std std-envvar docutils literal notranslate"><span class="pre">PYTHONDEVMODE</span></code></a> environment variable.</p>
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Last updated on Feb 26, 2021.
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