Utility method for defining enums.
    :param enums: Parameters of enumeration.
    :return: (Enum), the created enumerations.

def enum(**enums):
    """
    Utility method for defining enums.
    :param enums: Parameters of enumeration.
    :return: (Enum), the created enumerations.
    """
    enums['reverse'] = dict((value, key) for key, value in six.iteritems(enums))
    return type('Enum', (), enums)