reduce_generic_types.py

def _undo_type_conversion(obj):
    """
    Undo the conversion in typing._type_check().
    """
    if obj is type(None):
        return None
    else:
        return obj


def _reduce_typing_generic(self):
    import abc

    ns = dict(self.__dict__)
    tvars = ns.pop('__parameters__')
    args = ns.pop('__args__')
    origin = ns.pop('__origin__')
    extra = ns.pop('__extra__')
    orig_bases = ns.pop('__orig_bases__', None)
    assert origin is not None
    # Remove all generated stuff in namespace
    # Hopefully we are not missing anything here
    for k in list(ns):
        if k.startswith('__') and k.endswith('__'):
            del ns[k]
        elif k.startswith('_abc_'):
            del ns[k]
        elif k == '_gorg':
            del ns[k]
    # Fixup args
    args = tuple(map(_undo_type_conversion, args))
    # XXX sometimes extra is stuffed into bases, but not always, and I
    # don't know how to detect it
    # (try e.g. typing.Generator[int, None, None])
    bases = self.__bases__
    #if type(extra) is abc.ABCMeta:
        #bases = tuple(x for x in bases if x is not extra)
    return (self.__class__, (self.__name__, bases, ns,
                             tvars, args, origin, extra, orig_bases))