code: def horizontal_flip(im: np.ndarray) -> np.ndarray:
      """
      Flip the picture horizontally.
  
      Args:
          im(np.ndarray): Input image.
      """
      if len(im.shape) == 3:
          im = im[:, ::-1, :]
      elif len(im.shape) == 2:
          im = im[:, ::-1]
      return im
  
file_path: PaddleHub/paddlehub/vision/functional.py
imports: import os
  from typing import List, Union
  import cv2
  import PIL
  import numpy
label_desc: Use image node_id 5 for calling a global function with example usage: horizontal_flip(im) and returns: im