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Alternate implementation of pickle</TITLE>
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Alternate implementation of pickle">
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<H1><A NAME="SECTION005800000000000000000">
3.8 <tt class=module>cPickle</tt> --
         Alternate implementation of <tt class=module>pickle</tt></A>
</H1>

<P>


<P>
The <tt class=module>cPickle</tt> module provides a similar interface and identical
functionality as the <tt class=module><a href="module-pickle.html">pickle</a></tt> module, but can be up to 1000
times faster since it is implemented in C.  The only other
important difference to note is that <tt class=function>Pickler()</tt> and
<tt class=function>Unpickler()</tt> are functions and not classes, and so cannot be
subclassed.  This should not be an issue in most cases.

<P>
The format of the pickle data is identical to that produced using the
<tt class=module><a href="module-pickle.html">pickle</a></tt> module, so it is possible to use <tt class=module><a href="module-pickle.html">pickle</a></tt> and
<tt class=module>cPickle</tt> interchangably with existing pickles.

<P>
(Since the pickle data format is actually a tiny stack-oriented
programming language, and there are some freedoms in the encodings of
certain objects, it's possible that the two modules produce different
pickled data for the same input objects; however they will always be
able to read each others pickles back in.)
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