why drawing function in python-opencv return none?

Question

I want to draw somw shape on black background in python-opencv and show it but as I check drawing function is empty and imshow functon interrupt the code and I get error.

Answer 1

import cv2

img = cv2.imread("File Path")
cv2.rectangle(img, (x1, y1), (x2, y2), (255,0,0), 2)
cv2.imshow("lalala", img)
cv2.waitKey()

Just use this piece of code