docstr: returns the current observation from a frame
  
  :param frame: ([int] or [float]) environment frame
  :return: ([int] or [float]) the observation
docstr_tok: ["returns","the","current","observation","from","a","frame",":","param","frame",":","(","[","int","]","or","[","float","]",")","environment","frame",":","return",":","(","[","int","]","or","[","float","]",")","the","observation"]
code: def observation(self, frame):
      """
      returns the current observation from a frame
  
      :param frame: ([int] or [float]) environment frame
      :return: ([int] or [float]) the observation
      """
      frame = cv2.cvtColor(frame, cv2.COLOR_RGB2GRAY)
      frame = cv2.resize(
          frame, (self.width, self.height), interpolation=cv2.INTER_AREA
      )
      return frame[:, :, None]
  
imports: from collections import deque
  import numpy
  import gym
  from gym import spaces
  import cv2
label_desc: Use image node_id 2 for calling the WarpFrame obj's underlying member method code with example usage: obj.observation(frame) and returns: frame