
``copyreg`` --- Register ``pickle`` support functions
*****************************************************

The ``copyreg`` module provides support for the ``pickle`` module.
The ``copy`` module is likely to use this in the future as well.  It
provides configuration information about object constructors which are
not classes. Such constructors may be factory functions or class
instances.

copyreg.constructor(object)

   Declares *object* to be a valid constructor.  If *object* is not
   callable (and hence not valid as a constructor), raises
   ``TypeError``.

copyreg.pickle(type, function, constructor=None)

   Declares that *function* should be used as a "reduction" function
   for objects of type *type*.  *function* should return either a
   string or a tuple containing two or three elements.

   The optional *constructor* parameter, if provided, is a callable
   object which can be used to reconstruct the object when called with
   the tuple of arguments returned by *function* at pickling time.
   ``TypeError`` will be raised if *object* is a class or
   *constructor* is not callable.

   See the ``pickle`` module for more details on the interface
   expected of *function* and *constructor*.  Note that the
   ``dispatch_table`` attribute of a pickler object or subclass of
   ``pickle.Pickler`` can also be used for declaring reduction
   functions.
