#  _________________________________________________________________________
#
#  PyUtilib: A Python utility library.
#  Copyright (c) 2008 Sandia Corporation.
#  This software is distributed under the BSD License.
#  Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
#  the U.S. Government retains certain rights in this software.
#  _________________________________________________________________________


class MonoState(object):
    """A class where every instance shares state."""
    _state = {}

    def __new__(cls, *p, **k):
        self = object.__new__(cls, *p, **k)
        self.__dict__ = cls._state
        return self


class Singleton(object):
    """A class where the __new__() method returns the same instance."""

    def __new__(cls, *p, **k):
        if not '_the_instance' in cls.__dict__:
            cls._the_instance = object.__new__(cls)
        return cls._the_instance