def unique(enumeration):
    """Class decorator that ensures only unique members exist in an enumeration."""
    duplicates = []
    for name, member in enumeration.__members__.items():
        if name != member.name:
            duplicates.append((name, member.name))
    if duplicates:
        duplicate_names = ', '.join(
                ["%s -> %s" % (alias, name) for (alias, name) in duplicates]
                )
        raise ValueError('duplicate names found in %r: %s' %
                (enumeration, duplicate_names)
                )
    return enumeration
Class decorator that ensures only unique members exist in an enumeration.
kafka/vendor/enum34.py