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<h3>Enabling Future Features</h3>
<p>Starting in Python 2.1, new language features that affect compatibility with older versions of Python may be disabled when they first appear in a release. To enable these features, the statement <tT CLAss="monofont">from _ _ future_ _ import </tt><I><TT Class="monofont">feature</TT></I>
can be used. For example:</P>
<pre>
# Enable nested scopes in Python 2.1
from __ future __ import nested_scopes </pre>
<p>When used, this statement should appear as the first statement of a module or program. Furthermore, the intent of the <tt class="monofont">_ _ future_ _</tt> module is to introduce features that will eventually be a standard part of the Python language (in which case, the use of <tt clAss="monofont">_ _ future_ _</Tt> will not be required).</p>
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<P><TABLE width="100%" border=0><TR valign="top"><TD><font size=1 color="#C0C0C0"><br></font></TD><TD align=right><font size=1 color="#C0C0C0">Last updated on 3/28/2002<br>Python Essential Reference, Second Edition, © 2002 New Riders Publishing</font></TD></TR></TABLE></P>
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