Simple python3 youtube mp3 downloader

mp3Downloader.py

#### Windows 10 requirements ####
# -> python3 (from Microsoft Store (python 3.8) or official Python website)
# -> youtube_dl (Pip: pip install --upgrade youtube_dl)
# -> ffmpeg (Choco: choco install ffmpeg)
# Launch program with cmd: python3 path\to\mp3Downloader.py

from __future__ import unicode_literals
import youtube_dl
from tkinter import *

window = Tk()
label = Label(text = "YouTube URL: ")
entry = Entry(width = 50)
space1 = Label(text = "")
space2 = Label(text = "")

def mp3_download():
    url = entry.get()
    print(url)
    if url != "":
        try: 
            ydl_opts = {
                        'format': 'bestaudio/best',
                        'postprocessors': [{
                            'key': 'FFmpegExtractAudio',
                            'preferredcodec': 'mp3',
                            'preferredquality': '192',
                            }],
                        }
            with youtube_dl.YoutubeDL(ydl_opts) as ydl:
                ydl.download([url])
        except Exception:
            print("Invalid URL!")

dl_button = Button(master = window, text = "Download", command = mp3_download)
label.pack()
entry.pack()
space1.pack()
dl_button.pack()
space2.pack()
window.mainloop()