code: def translate_y_func(img, offset, fill=(0, 0, 0)):
      """
      same output as PIL.Image.transform
      """
      H, W = img.shape[0], img.shape[1]
      M = np.float32([[1, 0, 0], [0, 1, -offset]])
      out = cv2.warpAffine(
          img, M, (W, H), borderValue=fill, flags=cv2.INTER_LINEAR
      ).astype(np.uint8)
      return out
  
imports: import cv2
  import numpy
label_desc: Use image node_id 12 for calling a global function with example usage: translate_y_func(img, offset, fill) and returns: out