Saving numpy image frames to video with OpenCV

frames_to_video.py

import cv2
import numpy as np

def save_frames(frames, file_path, width, height, fps, codec="mp4v"):
  # Define the codec and create VideoWriter object
  fourcc = cv2.cv.CV_FOURCC(*codec)
  out = cv2.VideoWriter(file_path, fourcc, fps, (width,height))

  for frame in frames:
    out.write(frame)

thank you for your code !
run the code ,it's nothing?
thank you