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<div class="section" id="full-grammar-specification">
<h1>10. Full Grammar specification<a class="headerlink" href="https://elearning.szu.edu.cn/bbcswebdav/pid-394481-dt-content-rid-2786637_1/courses/201820192150306000201/Python%203.6.1%20BNF.htm#full-grammar-specification" title="Permalink to this headline">¶</a></h1>
<p>This is the full Python grammar, as it is read by the parser generator and used
to parse Python source files:</p>
<div class="highlight-python3"><div class="highlight"><pre><span></span><span class="c1"># Grammar for Python</span>
<span class="c1"># NOTE WELL: You should also follow all the steps listed at</span>
<span class="c1"># https://docs.python.org/devguide/grammar.html</span>
<span class="c1"># Start symbols for the grammar:</span>
<span class="c1"># single_input is a single interactive statement;</span>
<span class="c1"># file_input is a module or sequence of commands read from an input file;</span>
<span class="c1"># eval_input is the input for the eval() functions.</span>
<span class="c1"># NB: compound_stmt in single_input is followed by extra NEWLINE!</span>
<span class="n">single_input</span><span class="p">:</span> <span class="n">NEWLINE</span> <span class="o">|</span> <span class="n">simple_stmt</span> <span class="o">|</span> <span class="n">compound_stmt</span> <span class="n">NEWLINE</span>
<span class="n">file_input</span><span class="p">:</span> <span class="p">(</span><span class="n">NEWLINE</span> <span class="o">|</span> <span class="n">stmt</span><span class="p">)</span><span class="o">*</span> <span class="n">ENDMARKER</span>
<span class="n">eval_input</span><span class="p">:</span> <span class="n">testlist</span> <span class="n">NEWLINE</span><span class="o">*</span> <span class="n">ENDMARKER</span>
<span class="n">decorator</span><span class="p">:</span> <span class="s1">'@'</span> <span class="n">dotted_name</span> <span class="p">[</span> <span class="s1">'('</span> <span class="p">[</span><span class="n">arglist</span><span class="p">]</span> <span class="s1">')'</span> <span class="p">]</span> <span class="n">NEWLINE</span>
<span class="n">de
