import cv2

cap = cv2.VideoCapture('YouTube.mp4')

while cap.isOpened():
    ret, frame = cap.read()

    if ret:
        gray_frame = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
        cv2.imshow('frame', gray_frame)

    if cv2.waitKey(1) == 27:
        break

cap.release()
cv2.destroyAllWindows()