我收到此錯誤 -KeyError: <class '__main__.PublishPage'>這是我的代碼 -p = 0#Now, Adding the different pages for the gameclass HeadlineGame(tk.Tk):    def __init__(self, *args, **kwargs):        tk.Tk.__init__(self, *args, **kwargs)        container = tk.Frame(self)        container.pack(side="top", fill="both", expand=True)        container.grid_rowconfigure(0, weight=1)        container.grid_columnconfigure(0, weight=1)        self.frames = {}        frame = StartPage(container, self)        self.frames[StartPage] = frame        frame.grid(row=0, column=0, sticky="nsew")        self.show_frame(StartPage)    def show_frame(self, controller):        frame = self.frames[controller]        frame.tkraise()class StartPage(tk.Frame):    def __init__(self, parent, controller):        tk.Frame.__init__(self, parent)        publishbutton = tk.Button(self, image=publishimg, borderwidth=0, command= lambda: controller.show_frame(PublishPage))        publishbutton.image = publishimg        publishbutton.place(x=503, y=315)class PublishPage(tk.Frame):        def __init__(self, parent, controller):         button2 = tk.Button(self, text="Test")         button2.grid(row=0, column=0)app = HeadlineGame()app.geometry('1366x768')app.mainloop()我試圖解決這個問題，但無濟于事。這是 lambda 命令的問題嗎？我想要它，以便當我按下按鈕時，它會將我帶到第二幀，即使這個特定問題無法解決，有沒有辦法實現這一點？謝謝。編輯回溯錯誤：> Exception in Tkinter callback Traceback (most recent call last):   File> "C:\Users\DELL\AppData\Local\Programs\Python\Python38-32\lib\tkinter\__init__.py",> line 1883, in __call__>     return self.func(*args)   File "C:\Users\DELL\Desktop\Python\intro.py", line 276, in <lambda>>     publishbutton = tk.Button(self, image=publishimg, borderwidth=0, command= lambda: controller.show_frame(PublishPage))   File> "C:\Users\DELL\Desktop\Python\intro.py", line 197, in show_frame>     frame = self.frames[controller] KeyError: <class '__main__.PublishPage'>