'If the type of the key of a ``PMap`` is the same, but it has
internally changed then the output changes.'

def test_pmap_key_type_changed(self):

    class Different(CheckedPMap, ):
        __key_type__ = Subtype
        __value_type__ = int
    Original = Different
    class Different(CheckedPMap, ):
        __key_type__ = ChangedSubtype
        __value_type__ = int
    self.assert_catches_changes(Original, Different)
