def METHOD_NAME(self):
    st = typed_demo_asdl.Strings('', '')
    self.assertEqual('', st.required)
    self.assertEqual('', st.optional)
    # ZERO ARG "constructor" (static method)
    st = typed_demo_asdl.Strings.CreateNull(alloc_lists=True)
    self.assertEqual('', st.required)
    self.assertEqual(None, st.optional)
    # N arg constructor with None
    st = typed_demo_asdl.Strings('', None)
    self.assertEqual('', st.required)
    self.assertEqual(None, st.optional)