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<H3><A NAME="SECTION007233000000000000000"></A><A NAME="doctest-execution-context"></A>
<BR>
5.2.3.3 What's the Execution Context?
</H3>

<P>
By default, each time <tt class="module"><a href="module-doctest.html">doctest</a></tt> finds a docstring to test, it
uses a <em>shallow copy</em> of <tt class="module">M</tt>'s globals, so that running tests
doesn't change the module's real globals, and so that one test in
<tt class="module">M</tt> can't leave behind crumbs that accidentally allow another test
to work.  This means examples can freely use any names defined at top-level
in <tt class="module">M</tt>, and names defined earlier in the docstring being run.
Examples cannot see names defined in other docstrings.

<P>
You can force use of your own dict as the execution context by passing
<code>globs=your_dict</code> to <tt class="function">testmod()</tt> or
<tt class="function">testfile()</tt> instead.

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<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
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