reset() not working in python2

[shx2]

Try adding this unittest to tests_pyX/test_polyloader.py.
It works fine for python3, but fails for python27 ("Failed: DID NOT RAISE")

class Test_Polymorph_Reset(object):
    def test_reset_after_import(self):
        with ImportEnvironment() as sys:
            polyloader.install(compiler("2"), ['2'])
            polyloader.install(compiler("3"), ['3'])
            from tests_py2.polytestmix.test3 import result as result3
            polyloader.reset()
            with pytest.raises(ImportError):
                from tests_py2.polytestmix.test2 import result as result2
    def test_reset_before_import(self):
        with ImportEnvironment() as sys:
            polyloader.install(compiler("3"), ['3'])
            polyloader.reset()
            with pytest.raises(ImportError):
                from tests_py2.polytestmix.test3 import result as result3