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<FONT><h3>Metaclasses</h3>
<p>A <i>metaclass</I> is just a class that is used as a template to create class-like entities.</P>
<P>Normally, you create instances based on classes. The goal here is to create classes (<A name="idx1073743507"></A><I>metainstances</I>) based on other classes (<I>metaclasses</i>). The resulting metainstances are used as base classes for your own classes.</p>
<p>The whole idea is to offer you the possibility of operating Python's internal class-handling engine. Everything that usually happens behind the scenes while manipulating your classes and objects now can be accessed and changed. The meta instance makes it easier for you to handle the task of modifying the attribute lookup behavior of objects.</p>
<P>Prior to Python, version 1.5, it was necessary to use C extensions in order to define metaclasses.</P>
<P>The subsequent code defines a simple metaclass and its supporting classes. Note that this structure doesn't cover the whole model.</P>
<pre>
1: >>> import types
2: >>> class METACLASS:
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