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<FONT><h3>Polymorphism</h3>
<p>The concept of polymorphism doesn't really apply to Python objects because Python doesn't offer type declaration. This concept (having a function or method work for multiple argument types) is something you get for free with Python because of the dynamic typing. It does exist, but you don't usually explicitly code for it. When handling an <tT CLAss="monofont">obj.method</tt> expression, the meaning of <TT CLass="monofont">method</tT> depends on the type, or <I>class,</I> of the object <Tt class="monofont">obj.</tt></p>
<p>Python doesn't know what type of object implements an interface until the program is running. This feature is called <a name="idx1073743471"></a><a namE="idx1073743472"></a><i>runtime binding.</I></p>
<p>Python <a Name="idx1073743473"></a><A namE="idx1073743474"></A>variables are typed, just not explicitly so. They are typed implicitly as the program uses them. For instance, if a program invokes <TT clasS="monofont">abs(x),</TT> it doesn't make sense for <Tt claSS="monofont">x</TT> to be any object but a number. Therefore, the variable <tt clASS="monofont">x</Tt> is informally typed.</p>
<p>The capability of dealing with objects at different levels of abstraction is one of the most important features of object-oriented programming and a very important part of Python.</p>
<p>The next example shows how you can use just one function to implement poly morphism in Python. C++ refers to this variety of polymorphism as <a name="idx1073743475"></a><a name="idx1073743476"></a><a naMe="idx1073743477"></a><I>method overloading.</i></p>
<pRe>
>>> class polymorph:
卍ef handle_int(self, argint):
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