这道python题要怎样做，求

def _solution(arr, x):
    return arr.append(x)

1 import tkinter as tk

3 win = tk.Tk()
4 win.geometry("600x400+200+100")
5 canvas = tk.Canvas(win, bg="white")
6 canvas.place(relx=0.05, rely=0.05, relwidth=0.9, relheight=0.9)

8 win.mainloop()

Traceback (most recent call last):
File "G:/python/pythonProject/GUI/canvas.py", line 5, in
canvas = tk.Canvas(win, bg="white")
File "G:\python\python3.8.5\lib\tkinter_init.py", line 2683, in init
Widget.init(self, master, 'nvacas', cnf, kw)
File "G:\python\python3.8.5\lib\tkinter_init.py", line 2567, in init
self.tk.call(
_tkinter.TclError: invalid command name "nvacas"

这是为什么???