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<title>6.21.2.1 Understanding option actions</title>
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<H3><A NAME="SECTION0082121000000000000000"></A><A NAME="optparse-understanding-option-actions"></A>
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6.21.2.1 Understanding option actions
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<P>
Actions tell <tt class="module">optparse</tt> what to do when it encounters an option on the
command line. There is a fixed set of actions hard-coded into <tt class="module">optparse</tt>;
adding new actions is an advanced topic covered in section <A HREF="#optparse-extending"><tex2html_cross_ref_visible_mark></A>, Extending <tt class="module">optparse</tt>.
Most actions tell <tt class="module">optparse</tt> to store a value in some variable--for
example, take a string from the command line and store it in an
attribute of <code>options</code>.
<P>
If you don't specify an option action, <tt class="module">optparse</tt> defaults to <code>store</code>.
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<span class="release-info">Release 2.4.3, documentation updated on 29 March 2006.</span>
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