code: def testEnvProblem(self):
      # Register this class and expect to get it back.
  
      @registry.register_env_problem
      class EnvProb(object):
          batch_size = None
  
          def initialize(self, batch_size):
              self.batch_size = batch_size
  
      # Get it with given batch_size.
      batch_size = 100
      ep = registry.env_problem("env_prob", batch_size=batch_size)
  
      # name property is set.
      self.assertEqual("env_prob", ep.name)
  
      # initialize was called and therefore batch_size was set.
      self.assertEqual(batch_size, ep.batch_size)
  
      # assert on the type.
      self.assertIsInstance(ep, EnvProb)
  
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 2 for calling the EnvProblemRegistryTest obj's underlying member method code with example usage: obj.testEnvProblem() without return types