code: def test_uppercase(self):
      assert (
          string_utils.uppercase("this is a test") == "This is a test"
      )
      assert string_utils.uppercase("tEst") == "TEst"
  
imports: from parlai.core.opt import Opt
  from parlai.utils.misc import Timer, round_sigfigs, set_namedtuple_defaults, nice_report
  import parlai.utils.strings
  from copy import deepcopy
  import random
  import time
  import unittest
  from parlai.utils.data import DatatypeHelper
  from parlai.utils.curated_response import generate_init_prompot, generate_safe_response
label_desc: Use image node_id 3 for calling the TestStrings obj's underlying member method code with example usage: obj.test_uppercase() without return types