<!-- issue-number: [bpo-28617](https://www.bugs.python.org/issue28617) -->
https://bugs.python.org/issue28617
<!-- /issue-number -->
operator: not in
Two more operations with the same syntactic priority, :keyword:`in` and
-:keyword:`not in`, are supported only by sequence types (below).
-
+:keyword:`not in`, are supported by types that are :term:`iterable` or
+implement the :meth:`__contains__` method.
.. _typesnumeric:
--- /dev/null
+Fixed info in the stdtypes docs concerning the types that support membership
+tests.