code: def _get_obs(self):
      theta = self.sim.data.qpos.flat[:2]
      return np.concatenate(
          [
              np.cos(theta),
              np.sin(theta),
              self.sim.data.qpos.flat[2:],
              self.sim.data.qvel.flat[:2],
              self.get_body_com("fingertip")
              - self.get_body_com("target"),
          ]
      )
  
file_path: gym/gym/envs/mujoco/reacher.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 ReacherEnv obj's underlying member method code with example usage: obj._get_obs() and returns: np