code: def _get_observation(self, state_desc):
      pass
  
imports: import abc
  import gym
  import math
  import numpy
  import random
  from collections import OrderedDict
  from osim.env import ProstheticsEnv
  from parl.utils import logger
  from tqdm import tqdm
label_desc: Use image node_id 3 for calling the ObsTranformerBase obj's underlying member method code with example usage: obj._get_observation(state_desc) without return types