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<title>3.14 pickle -- Python object serialization
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<H1><A NAME=
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3.14 <tt class=
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</tt> -- Python object serialization
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The
<tt class=
"module">pickle
</tt> module implements a fundamental, but powerful
algorithm for serializing and de-serializing a Python object
structure. ``Pickling'' is the process whereby a Python object
hierarchy is converted into a byte stream, and ``unpickling'' is the
inverse operation, whereby a byte stream is converted back into an
object hierarchy. Pickling (and unpickling) is alternatively known as
``serialization'', ``marshalling,''
<A NAME=
"tex2html14"
HREF=
"#foot8963"><SUP>3.2</SUP></A> or ``flattening'',
however, to avoid confusion, the terms used here are ``pickling'' and
This documentation describes both the
<tt class=
"module">pickle
</tt> module and the
<tt class=
"module"><a href=
"module-cPickle.html">cPickle
</a></tt> module.
<BR><HR><H4>Footnotes
</H4>
<DT><A NAME=
"foot8963">... ``marshalling,''
</A><A
href=
"module-pickle.html#tex2html14"><SUP>3.2</SUP></A></DT>
<DD>Don't confuse this with
the
<tt class=
"module"><a href=
"module-marshal.html">marshal
</a></tt> module
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<A NAME=
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</STRONG></a>
<LI><A href=
"node63.html">3.14.1 Relationship to other Python modules
</a>
<LI><A href=
"node64.html">3.14.2 Data stream format
</a>
<LI><A href=
"node65.html">3.14.3 Usage
</a>
<LI><A href=
"node66.html">3.14.4 What can be pickled and unpickled?
</a>
<LI><A href=
"pickle-protocol.html">3.14.5 The pickle protocol
</a>
<LI><A href=
"pickle-inst.html">3.14.5.1 Pickling and unpickling normal class
<LI><A href=
"node69.html">3.14.5.2 Pickling and unpickling extension types
</a>
<LI><A href=
"node70.html">3.14.5.3 Pickling and unpickling external objects
</a>
<LI><A href=
"pickle-sub.html">3.14.6 Subclassing Unpicklers
</a>
<LI><A href=
"pickle-example.html">3.14.7 Example
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