code: def testListModels(self):
      @registry.register_model
      def m1():
          pass
  
      @registry.register_model
      def m2():
          pass
  
      self.assertSetEqual(
          set(["m1", "m2"]), set(registry.list_models())
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from tensor2tensor.utils import registry
  from tensor2tensor.utils import t2t_model
  import tensorflow.compat.v1
label_desc: Use image node_id 7 for calling the ModelRegistryTest obj's underlying member method code with example usage: obj.testListModels() without return types