code: def test_str(self) -> None:
      self.assertEqual(
          str(Stats(my_int_metric=1, my_float_metric=0.2, count=3)),
          "my_int_metric:  1 , my_float_metric:  0.2 , count:  3",
      )
  
imports: from unittest import main, TestCase
  from torchbiggraph.stats import Stats
label_desc: Use image node_id 3 for calling the TestConfig obj's underlying member method code with example usage: obj.test_str() without return types