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Editors and IDEs" accesskey="P">previous</a> |</li> <li><img src="../_static/py.svg" alt="Python logo" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="https://www.python.org/">Python</a> »</li> <li class="switchers"> <div class="language_switcher_placeholder"></div> <div class="version_switcher_placeholder"></div> </li> <li> </li> <li id="cpython-language-and-version"> <a href="../index.html">3.13.2 Documentation</a> » </li> <li class="nav-item nav-item-this"><a href="">The Python Language Reference</a></li> <li class="right"> <div class="inline-search" role="search"> <form class="inline-search" action="../search.html" method="get"> <input placeholder="Quick search" aria-label="Quick search" type="search" name="q" id="search-box" /> <input type="submit" value="Go" /> </form> </div> | </li> <li class="right"> <label class="theme-selector-label"> Theme <select class="theme-selector" oninput="activateTheme(this.value)"> <option value="auto" selected>Auto</option> <option value="light">Light</option> <option value="dark">Dark</option> </select> </label> |</li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body" role="main"> <section id="the-python-language-reference"> <span id="reference-index"></span><h1>The Python Language Reference<a class="headerlink" href="#the-python-language-reference" title="Link to this heading">¶</a></h1> <p>This reference manual describes the syntax and “core semantics” of the language. It is terse, but attempts to be exact and complete. The semantics of non-essential built-in object types and of the built-in functions and modules are described in <a class="reference internal" href="../library/index.html#library-index"><span class="std std-ref">The Python Standard Library</span></a>. For an informal introduction to the language, see <a class="reference internal" href="../tutorial/index.html#tutorial-index"><span class="std std-ref">The Python Tutorial</span></a>. For C or C++ programmers, two additional manuals exist: <a class="reference internal" href="../extending/index.html#extending-index"><span class="std std-ref">Extending and Embedding the Python Interpreter</span></a> describes the high-level picture of how to write a Python extension module, and the <a class="reference internal" href="../c-api/index.html#c-api-index"><span class="std std-ref">Python/C API Reference Manual</span></a> describes the interfaces available to C/C++ programmers in detail.</p> <div class="toctree-wrapper compound"> <ul> <li class="toctree-l1"><a class="reference internal" href="introduction.html">1. Introduction</a><ul> <li class="toctree-l2"><a class="reference internal" href="introduction.html#alternate-implementations">1.1. Alternate Implementations</a></li> <li class="toctree-l2"><a class="reference internal" href="introduction.html#notation">1.2. Notation</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="lexical_analysis.html">2. Lexical analysis</a><ul> <li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#line-structure">2.1. Line structure</a></li> <li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#other-tokens">2.2. Other tokens</a></li> <li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#identifiers">2.3. Identifiers and keywords</a></li> <li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#literals">2.4. Literals</a></li> <li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#operators">2.5. Operators</a></li> <li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#delimiters">2.6. Delimiters</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="datamodel.html">3. Data model</a><ul> <li class="toctree-l2"><a class="reference internal" href="datamodel.html#objects-values-and-types">3.1. Objects, values and types</a></li> <li class="toctree-l2"><a class="reference internal" href="datamodel.html#the-standard-type-hierarchy">3.2. The standard type hierarchy</a></li> <li class="toctree-l2"><a class="reference internal" href="datamodel.html#special-method-names">3.3. Special method names</a></li> <li class="toctree-l2"><a class="reference internal" href="datamodel.html#coroutines">3.4. Coroutines</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="executionmodel.html">4. Execution model</a><ul> <li class="toctree-l2"><a class="reference internal" href="executionmodel.html#structure-of-a-program">4.1. Structure of a program</a></li> <li class="toctree-l2"><a class="reference internal" href="executionmodel.html#naming-and-binding">4.2. Naming and binding</a></li> <li class="toctree-l2"><a class="reference internal" href="executionmodel.html#exceptions">4.3. Exceptions</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="import.html">5. The import system</a><ul> <li class="toctree-l2"><a class="reference internal" href="import.html#importlib">5.1. <code class="xref py py-mod docutils literal notranslate"><span class="pre">importlib</span></code></a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#packages">5.2. Packages</a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#searching">5.3. Searching</a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#loading">5.4. Loading</a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#the-path-based-finder">5.5. The Path Based Finder</a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#replacing-the-standard-import-system">5.6. Replacing the standard import system</a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#package-relative-imports">5.7. Package Relative Imports</a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#special-considerations-for-main">5.8. Special considerations for __main__</a></li> <li class="toctree-l2"><a class="reference internal" href="import.html#references">5.9. References</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="expressions.html">6. Expressions</a><ul> <li class="toctree-l2"><a class="reference internal" href="expressions.html#arithmetic-conversions">6.1. Arithmetic conversions</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#atoms">6.2. Atoms</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#primaries">6.3. Primaries</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#await-expression">6.4. Await expression</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#the-power-operator">6.5. The power operator</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#unary-arithmetic-and-bitwise-operations">6.6. Unary arithmetic and bitwise operations</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#binary-arithmetic-operations">6.7. Binary arithmetic operations</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#shifting-operations">6.8. Shifting operations</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#binary-bitwise-operations">6.9. Binary bitwise operations</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#comparisons">6.10. Comparisons</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#boolean-operations">6.11. Boolean operations</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#assignment-expressions">6.12. Assignment expressions</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#conditional-expressions">6.13. Conditional expressions</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#lambda">6.14. Lambdas</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#expression-lists">6.15. Expression lists</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#evaluation-order">6.16. Evaluation order</a></li> <li class="toctree-l2"><a class="reference internal" href="expressions.html#operator-precedence">6.17. Operator precedence</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="simple_stmts.html">7. Simple statements</a><ul> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#expression-statements">7.1. Expression statements</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#assignment-statements">7.2. Assignment statements</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-assert-statement">7.3. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">assert</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-pass-statement">7.4. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">pass</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-del-statement">7.5. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">del</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-return-statement">7.6. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">return</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-yield-statement">7.7. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">yield</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-raise-statement">7.8. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">raise</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-break-statement">7.9. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">break</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-continue-statement">7.10. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">continue</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-import-statement">7.11. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">import</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-global-statement">7.12. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">global</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-nonlocal-statement">7.13. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">nonlocal</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-type-statement">7.14. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">type</span></code> statement</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="compound_stmts.html">8. Compound statements</a><ul> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-if-statement">8.1. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">if</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-while-statement">8.2. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">while</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-for-statement">8.3. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">for</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-try-statement">8.4. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">try</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-with-statement">8.5. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-match-statement">8.6. The <code class="xref std std-keyword docutils literal notranslate"><span class="pre">match</span></code> statement</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#function-definitions">8.7. Function definitions</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#class-definitions">8.8. Class definitions</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#coroutines">8.9. Coroutines</a></li> <li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#type-parameter-lists">8.10. Type parameter lists</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="toplevel_components.html">9. Top-level components</a><ul> <li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#complete-python-programs">9.1. Complete Python programs</a></li> <li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#file-input">9.2. File input</a></li> <li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#interactive-input">9.3. Interactive input</a></li> <li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#expression-input">9.4. Expression input</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="grammar.html">10. Full Grammar specification</a></li> </ul> </div> </section> <div class="clearer"></div> </div> </div> </div> <div class="sphinxsidebar" role="navigation" aria-label="Main"> <div class="sphinxsidebarwrapper"> <div> <h4>Previous topic</h4> <p class="topless"><a href="../using/editors.html" title="previous chapter"><span class="section-number">8. </span>Editors and IDEs</a></p> </div> <div> <h4>Next topic</h4> <p class="topless"><a href="introduction.html" title="next chapter"><span class="section-number">1. </span>Introduction</a></p> </div> <div role="note" aria-label="source link"> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../bugs.html">Report a Bug</a></li> <li> <a href="https://github.com/python/cpython/blob/main/Doc/reference/index.rst" rel="nofollow">Show Source </a> </li> </ul> </div> </div> <div id="sidebarbutton" title="Collapse sidebar"> <span>«</span> </div> </div> <div class="clearer"></div> </div> <div class="related" role="navigation" aria-label="Related"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" >index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="introduction.html" title="1. 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