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<H2><A NAME="SECTION0052110000000000000000"></A>
<A NAME="examples-imp"></A>
<BR>
3.21.1 Examples
</H2>

<P>
The following function emulates what was the standard import statement
up to Python 1.4 (no hierarchical module names).  (This
<em>implementation</em> wouldn't work in that version, since
<tt class="function">find_module()</tt> has been extended and
<tt class="function">load_module()</tt> has been added in 1.4.)

<P>
<div class="verbatim"><pre>
import imp
import sys

def __import__(name, globals=None, locals=None, fromlist=None):
    # Fast path: see if the module has already been imported.
    try:
        return sys.modules[name]
    except KeyError:
        pass

    # If any of the following calls raises an exception,
    # there's a problem we can't handle -- let the caller handle it.

    fp, pathname, description = imp.find_module(name)

    try:
        return imp.load_module(name, fp, pathname, description)
    finally:
        # Since we may exit via an exception, close fp explicitly.
        if fp:
            fp.close()
</pre></div>

<P>
A more complete example that implements hierarchical module names and
includes a <tt class="function">reload()</tt><a id='l2h-723' xml:id='l2h-723'></a> function can be
found in the module <tt class="module">knee</tt><a id='l2h-724' xml:id='l2h-724'></a>.  The
<tt class="module">knee</tt> module can be found in <span class="file">Demo/imputil/</span> in the
Python source distribution.

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