human
Complete this python program:
def enum(enum_type='enum', base_classes=None, methods=None, **attrs):
assistant
#Here is the Python code you requested.

    """Generates a enumeration with the given attributes.
    """
    def __init__(instance, *args, **kwargs):
        raise RuntimeError(('%s    types    can    not    be    initialized.' % enum_type))
    if (base_classes is None):
        base_classes = ()
    if (methods is None):
        methods = {}
    base_classes = (base_classes + (object,))
    for (k, v) in methods.items():
        methods[k] = classmethod(v)
    attrs['enums'] = attrs.copy()
    methods.update(attrs)
    methods['__init__'] = __init__
    return type(to_string(enum_type), base_classes, methods)