code: def step_single(self):
      assert_equals(self.str_param, "does this work?")
      assert_equals(self.nondefault_param, False)
      assert_equals(self.json_param, {"a": [8]})
  
imports: from metaflow_test import MetaflowTest, ExpectationFailed, steps
label_desc: Use image node_id 1 for calling the DynamicParameterTest obj's underlying member method code with example usage: obj.step_single() without return types