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<H1><A NAME="SECTION008100000000000000000"></A><A NAME="exprstmts"></A>
<BR>
6.1 Expression statements
</H1>
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<P>
Expression statements are used (mostly interactively) to compute and
write a value, or (usually) to call a procedure (a function that
returns no meaningful result; in Python, procedures return the value
<code>None</code>).  Other uses of expression statements are allowed and
occasionally useful.  The syntax for an expression statement is:

<P>
<dl><dd class="grammar">
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<table>
<tr>
    <td><a id='tok-expression_stmt' xml:id='tok-expression_stmt'>expression_stmt</a></td>
    <td>::=</td>
    <td><a class='grammartoken' href="exprlists.html#tok-expression_list">expression_list</a></td></tr>
</table>
</div>
<a class="grammar-footer"
  href="grammar.txt" type="text/plain"
  >Download entire grammar as text.</a>
</dd></dl>

<P>
An expression statement evaluates the expression list (which may be a
single expression).
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In interactive mode, if the value is not <code>None</code>, it is converted
to a string using the built-in <tt class="function">repr()</tt><a id='l2h-454' xml:id='l2h-454'></a>function and the resulting string is written to standard output (see
section&nbsp;<A href="print.html#print">6.6</A>) on a line by itself.  (Expression statements
yielding <code>None</code> are not written, so that procedure calls do not
cause any output.)
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<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
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