code: def viewer_setup(self):
      assert self.viewer is not None
      self.viewer.cam.distance = self.model.stat.extent * 0.5
  
file_path: gym/gym/envs/mujoco/ant.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 AntEnv obj's underlying member method code with example usage: obj.viewer_setup() without return types