mp3.py

# importing packages
from pytube import YouTube
import os

while True:
	# url input from user
	yt = YouTube(
		str(input("Enter the URL of the video you want to download: \n>> ")))

	# extract only audio
	video = yt.streams.filter(only_audio=True).first()

	# check for destination to save file
	print("Enter the destination (leave blank for current directory)")
	destination = str(input(">> ")) or 'Downloads'

	# download the file
	out_file = video.download(output_path=destination)

	# save the file
	base, ext = os.path.splitext(out_file)
	new_file = base + '.mp3'
	os.rename(out_file, new_file)

	# result of success
	print(yt.title + " has been successfully downloaded.")

	continue_operation = input("Would you like to continue? y/n: ")
	if continue_operation == "n":
		break