refactor, explain and improve this python code:
import winsound
import random
import threading
import tkinter as tk
from tkinter import filedialog
import vlc
def play_metronome():
    while True:
        bpm = random.randint(30, 150)
        interval = 60 / bpm
        winsound.PlaySound("I:/metronome.wav", winsound.SND_FILENAME | winsound.SND_ASYNC)
        threading.Timer(interval * 5, play_metronome).start()
        break
def play_video():
    video_file = filedialog.askopenfilename(filetypes=[("Video files", "*.mp4;*.avi;*.mkv")])
    media = vlc_instance.media_new(video_file)
    player.set_media(media)
    player.play()
    player.audio_toggle_mute()
def stop_video():
    player.stop()
vlc_instance = vlc.Instance()
player = vlc_instance.media_player_new()
root = tk.Tk()
root.title("beat Hero")
play_button = tk.Button(root, text="Play Video", command=play_video)
play_button.pack()
stop_button = tk.Button(root, text="Stop Video", command=stop_video)
stop_button.pack()
metronome_thread = threading.Thread(target=play_metronome, daemon=True)
metronome_thread.start()
root.mainloop()