Jeff Epler c60589c02b py/objtype: Fix assertion failures in super_attr by checking type.
Fixes assertion failures and segmentation faults when making calls like:

    super(1, 1).x
2018-05-30 11:14:07 +10:00
..
2014-03-31 18:02:22 +01:00
2014-03-31 22:57:56 +01:00
2017-05-29 11:36:05 +03:00
2014-02-10 07:13:32 +02:00
2014-04-13 17:46:30 +01:00