code: def policy(self, obs):
      return self.actor_model.policy(obs)
  
file_path: PARL/benchmark/fluid/DDPG/mujoco_model.py
imports: import paddle.fluid
  import parl
  from parl import layers
label_desc: Use image node_id 2 for calling the MujocoModel obj's underlying member method code with example usage: obj.policy(obs) and returns: self