class_docstr: Add SNR noise [-1, 1]
code: def get_power(self, clip):
      clip2 = clip.copy()
      clip2 = clip2**2
      return np.sum(clip2) / (len(clip2) * 1.0)
  
imports: import random
  import cv2
  import numpy
  import torch
  from scipy import signal
label_desc: Use image node_id 2 for calling the AddNoise obj's underlying member method code with example usage: obj.get_power(clip) and returns: unknown