code: def policy_sample(self, obs):
      return self.policy_model.sample(obs)
  
file_path: PARL/benchmark/fluid/PPO/mujoco_model.py
imports: import numpy
  import parl
  from parl import layers
  from paddle import fluid
  from paddle.fluid.param_attr import ParamAttr
label_desc: Use image node_id 3 for calling the MujocoModel obj's underlying member method code with example usage: obj.policy_sample(obs) and returns: self