Tkinter, асинхронность

from tkinter import *
import vk
import urllib.request
from tkinter import messagebox
import os
 
 
def create_window():
    messagebox.showinfo('Some Error', 'Error')
def output(event):
     session=vk.Session(access_token=*********************')
     api=vk.API(session)
     koltrackov = ent.get()
     se=api.audio.get(count=koltrackov)
     ko=0
     listbox.delete(0, END)
     for x in se:
         x=x['artist']
         listbox.insert(END,x)
         listbox.insert(END,'\n')
def on_select(event):
     try:
          
          session=vk.Session(access_token='*******************************************************************************')
          api=vk.API(session)
          se=api.audio.get()
          baza=[]
          sh=0
          for x in se:
               baza.append(x['artist'])
               baza.append(x['url'])
          index = listbox.curselection()[0]
          seltext = listbox.get(index)
          sh=baza.index(seltext)
          sh=sh+1
          req = urllib.request.urlopen(baza[sh])
          data = req.read()
          nametracke=baza[sh-1]
          f = open(nametracke + '.mp3', 'wb')
          f.write(data)
          f.close()
          
     except ValueError:
          create_window()
     except urllib.error.URLError as e:
          create_window()         
master = Tk()
ent = Entry(master,width=7)
scrollbar = Scrollbar(master)
scrollbar.pack(side=RIGHT, fill=Y)
listbox = Listbox(master,width=70, height=40, yscrollcommand=scrollbar.set)
w = Label(master, text="Какое количество Треков")
listbox.pack(side=LEFT, fill=BOTH)
but=Button(master,text="Показать Музыку",width=15)
scrollbar.config(command=listbox.yview)
but.bind("<Button-1>",output)
listbox.bind('<<ListboxSelect>>', on_select)
but.pack()
w.pack(side='bottom')
ent.pack(side='bottom')
master.mainloop()