def METHOD_NAME(self):
    # GIVEN
    gcs_object = self._monkeypatch_gcsobject(GCSObject('test/dir1/dir2/'))
    gcs_object.client.create_bucket('test')
    # WHEN
    gcs_object.mkdir()
    # THEN
    self.assertTrue(gcs_object.bucket.get_blob('dir1/dir2/'))