Constants in Python

const.py

# http://code.activestate.com/recipes/65207-constants-in-python/?in=user-97991


class _const(object):

    class ConstError(TypeError):
        pass

    class ConstCaseError(ConstError):
        pass

    def __setattr__(self, name, value):

        if name in self.__dict__:
            raise self.ConstError, "Can't rebind const({0})".format(name)

        if not name.isupper():
            raise self.ConstCaseError, 'const name {0} is not all uppercase'.format(name)

        self.__dict__[name] = value

import sys
# http://stackoverflow.com/questions/5365562/why-is-the-value-of-name-changing-after-assignment-to-sys-modules-name
# ref = sys.modules['__main__']
sys.modules[__name__] = _const()