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<title>2.3.10.1 Modules
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<H3><A NAME=
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"typesmodules"></A>
The only special operation on a module is attribute access:
<code><var>m
</var>.
<var>name
</var></code>, where
<var>m
</var> is a module and
<var>name
</var>
accesses a name defined in
<var>m
</var>'s symbol table. Module attributes
can be assigned to. (Note that the
<tt class=
"keyword">import
</tt> statement is not,
strictly speaking, an operation on a module object;
<code>import
<var>foo
</var></code> does not require a module object named
<var>foo
</var> to exist,
rather it requires an (external)
<em>definition
</em> for a module named
<var>foo
</var> somewhere.)
A special member of every module is
<tt class=
"member">__dict__
</tt>.
This is the dictionary containing the module's symbol table.
Modifying this dictionary will actually change the module's symbol
table, but direct assignment to the
<tt class=
"member">__dict__
</tt> attribute is not
possible (you can write
<code><var>m
</var>.__dict__['a'] =
1</code>, which
defines
<code><var>m
</var>.a
</code> to be
<code>1</code>, but you can't write
<code><var>m
</var>.__dict__ = {}
</code>). Modifying
<tt class=
"member">__dict__
</tt> directly
Modules built into the interpreter are written like this:
<code><module 'sys' (built-in)
></code>. If loaded from a file, they are
written as
<code><module 'os' from
'/usr/local/lib/python2.4/os.pyc'
></code>.
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<span class=
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2.4.2, documentation updated on
28 September
2005.
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