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#pip install pafy
#sudo pip install --upgrade youtube_dl
import cv2, pafy

url   = "https://www.youtube.com/watch______"
video = pafy.new(url)
best  = video.getbest(preftype="webm")
#documentation: https://pypi.org/project/pafy/

capture = cv2.VideoCapture(best.url)

Mxhmovd

#change KEY_PATH, API_KEY, LIST_ID
#API_KEY https://blog.hubspot.com/website/how-to-get-youtube-api-key
#KEY_PATH https://cloud.google.com/docs/authentication/getting-started
#LIST_ID for ex. list_id in https://www.youtube.com/watch?v=fjYptQjF1Tw&list=RDfjYptQjF1Tw&start_radio=1 is "RDfjYptQjF1Tw"

import os
from googleapiclient.discovery import build

credential_path = "KEY_PATH"
os.environ['GOOGLE_APPLICATION_CREDENTIALS'] = credential_path