code: def _get_obs(self):
      position = self.sim.data.qpos.flat.copy()
      velocity = self.sim.data.qvel.flat.copy()
  
      if self._exclude_current_positions_from_observation:
          position = position[2:]
  
      observation = np.concatenate([position, velocity]).ravel()
      return observation
  
file_path: gym/gym/envs/mujoco/swimmer_v3.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 4 for calling the SwimmerEnv obj's underlying member method code with example usage: obj._get_obs() and returns: observation