code: def test_rmod(self):
      class ustr2(UserString):
          pass
  
      class ustr3(ustr2):
          def __rmod__(self, other):
              return super().__rmod__(other)
  
      fmt2 = ustr2("value is %s")
      str3 = ustr3("TEST")
      self.assertEqual(fmt2 % str3, "value is TEST")
  
file_path: cpython/Lib/test/test_userstring.py
imports: import unittest
  from test import string_tests
  from collections import UserString
label_desc: Use image node_id 4 for calling the UserStringTest obj's underlying member method code with example usage: obj.test_rmod() and returns: super