class_docstr: Base class for TFEnvrionment wrappers.
code: def _current_time_step(self):
      return self._env.current_time_step()
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow
  from tf_agents.environments import tf_environment
  from tf_agents.specs import tensor_spec
label_desc: Use image node_id 8 for calling the TFEnvironmentBaseWrapper obj's underlying member method code with example usage: obj._current_time_step() and returns: self