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:mod:`pickletools` --- Tools for pickle developers
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.. module:: pickletools
:synopsis: Contains extensive comments about the pickle protocols and pickle-machine
opcodes, as well as some useful functions.
.. versionadded:: 2.3
**Source code:** :source:`Lib/pickletools.py`
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This module contains various constants relating to the intimate details of the
:mod:`pickle` module, some lengthy comments about the implementation, and a few
useful functions for analyzing pickled data. The contents of this module are
useful for Python core developers who are working on the :mod:`pickle` and
:mod:`cPickle` implementations; ordinary users of the :mod:`pickle` module
probably won't find the :mod:`pickletools` module relevant.
.. function:: dis(pickle, out=None, memo=None, indentlevel=4)
Outputs a symbolic disassembly of the pickle to the file-like object *out*,
defaulting to ``sys.stdout``. *pickle* can be a string or a file-like object.
*memo* can be a Python dictionary that will be used as the pickle's memo; it can
be used to perform disassemblies across multiple pickles created by the same
pickler. Successive levels, indicated by ``MARK`` opcodes in the stream, are
indented by *indentlevel* spaces.
.. function:: genops(pickle)
Provides an :term:`iterator` over all of the opcodes in a pickle, returning a
sequence of ``(opcode, arg, pos)`` triples. *opcode* is an instance of an
:class:`OpcodeInfo` class; *arg* is the decoded value, as a Python object, of
the opcode's argument; *pos* is the position at which this opcode is located.
*pickle* can be a string or a file-like object.
.. function:: optimize(picklestring)
Returns a new equivalent pickle string after eliminating unused ``PUT``
opcodes. The optimized pickle is shorter, takes less transmission time,
requires less storage space, and unpickles more efficiently.
.. versionadded:: 2.6