无法使用asksaveas函数

Question

我正在制作一个GUI应用程序，用户可以从youtube下载任何视频，下面是我使用的代码：

from pytube import YouTube
from tkinter import *
from tkinter import messagebox
from tkinter.filedialog import *
from threading import *

root=Tk()

root.iconbitmap('yticon.ico')
root.title('Youtube Video Downloader')
root.resizable(0,0)

file_size=0
url=''

def downThread():
    p1=Thread(target=downloader)
    p1.start()
def progress(chunk,file_handle,remaining):
    global download_status
    file_download=file_size-remaining
    per=(file_download/file_size)*100
    download_status.config(text='{:00.0f}% downloaded'.format(per))

def downloader():
    global file_size, download_status, url
    download_btn.config(state=DISABLED)
    download_status.place(x=200, y=250)
    #try:
    link=url.get()
    path=asksaveasfilename(title='Save File', defaultextension='.mp4', filetype=(('*.mp4', 'MP4 Files')))
    yt=YouTube(link, on_progress_callback=progress)
    video=yt.streams.filter(progressive=True, file_extension='mp4').first()
    file_size=video.filesize
    #assert isinstance(video, bytes)
    video.download(path)
    download_status.config(text='Download Finished...')
    res=messagebox.askyesno('Youtube Downloader','Do You want to download another video?')
    if res==1:
        url.delete(0,END)
        download_btn.config(state=NORMAL)
        download_status.config(text=' ')
    else:
        root.destroy()
    #except Exception as e:
     #   download_status.config(text='Failed!!There was an error')

imgfile=PhotoImage(file='yticon1.png')
back_img=Label(root, image=imgfile)
back_img.place(x=0,y=0,relwidth=1,relheight=1)
entr_url=Label(root, text='Enter Url', font='Algerian 15 bold')
entr_url.place(x=20,y=40)
url=Entry(root, width=30, bd=2, relief=SUNKEN, font=('Calibiri(Body)', 12))
url.place(x=140, y=40)
btnimg=PhotoImage(file='yt.png')
download_btn=Button(root, width=99, height=50, relief=RIDGE, activebackground='red', image=btnimg, command=downThread, bd=7)
download_btn.place(x=220, y=170)
download_status=Label(root, text='Please Wait...', font=('Arial',15))
root.geometry('700x400+150+150')
root.mainloop()

但是当我运行这段代码时，它给出了这个错误，我该如何解决它呢？

_tkinter.TclError: bad file type ".mp4", should be "typeName {extension ?extensions ...?} ?{macType ?macTypes ...?}?"

Answer 1

link=url.get()

path=asksaveasfilename(title='Save File', defaultextension='.mp4',filetype=(('*.mp4', 'MP4 Files')))

yt=YouTube(link，on_progress_callback=progress) ('*.mp4'，'mp4文件‘))`您必须这样做，因为文件类型将是列表形式。