code: def viewer_setup(self):
      assert self.viewer is not None
      v = self.viewer
      v.cam.trackbodyid = 0
      v.cam.distance = self.model.stat.extent * 0.5
      v.cam.lookat[2] = 0.12250000000000005
  
file_path: gym/gym/envs/mujoco/inverted_double_pendulum.py
imports: import numpy
  from gym import utils
  from gym.envs.mujoco import MuJocoPyEnv
  from gym.spaces import Box
label_desc: Use image node_id 5 for calling the InvertedDoublePendulumEnv obj's underlying member method code with example usage: obj.viewer_setup() without return types