human
I wrote the below code

    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)

What's a good function header?
assistant
#Here's a good function header.

def enum(enum_type='enum', base_classes=None, methods=None, **attrs):