youtube_downloader_cli.py

from pytube import YouTube


# the function takes the video url as an argument
def video_downloader(video_url):

    # passing the url to the YouTube object
    my_video = YouTube(video_url)

    # downloading the video in high resolution
    my_video.streams.get_highest_resolution().download()

    # return the video title
    return my_video.title

# the try statement will run if there are no errors
try:
    # getting the url from the user
    youtube_link = input('Enter the YouTube link:')
    
    print(f'Downloading your Video, please wait.......')
    
    # passing the url to the function
    video = video_downloader(youtube_link)
    # printing the video title
    print(f'"{video}" downloaded succussfully!!')
    
#the except will catch ValueError, URLError, RegexMatchError and simalar
except:
    print(f'Failed to download video\nThe '\
          'following might be the causes\n->No internet '\
          'connection\n->Invalid video link')
    
    
# YouTube(url).streams.filter(res="360p").first().download()

#YouTube(url).streams.first().download()