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<H2>
<BR>
3.17.1 Examples
</H2>
<P>
The following function emulates what was the standard import statement
up to Python 1.4 (i.e., no hierarchical module names). (This
<i>implementation</i> 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>
<dl><dd><pre class="verbatim">
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></dl>
<P>
A more complete example that implements hierarchical module names and
includes a <tt class="function">reload()</tt> function can be
found in the standard module <tt class="module">knee</tt> (which
is intended as an example only -- don't rely on any part of it being
a standard interface).
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