:mod:`pickletools` --- Tools for pickle developers ================================================== .. 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` -------------- 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