title: Hiding Label from on one Class by pressing a Button in another Class
body: <p>I have an idea to create a simple scoreboard app (sport) with two windows (creating in Tkinter). One is for controlling and another one for output information.</p>
  
  <p>So the idea is that I press button "show scoreboard" in a tk.Toplevel window and it appears in the main app window. And as I press hide, it hides. I know that I can create it just writing script without Classes and just like hundreds def strings but I want to use OOP as I would like to start programming the right way. </p>
  
  <p>My problem is that when I press "Hide the scoreboard" (I create Labels for scoreboard) label is not hiding. Any suggestions?</p>
  
  <p>I know that commands and defs must be in the same "tree", but how to arrange it when using the OOP.</p>
  
  <p>So here is my code</p>
  
  <pre><code>import tkinter as tk
  
  def forget():
  scoreboard.pack_forget()
  
  class Main(tk.Tk):
      def __init__(self):
          super().__init__()
          self.title("Scorebug")
          self.geometry("500x300")
          self.configure(background="green")
          scoreboard = tk.Label(self, text="This is like scoreboard")
          scoreboard.pack()
  
  class Control(tk.Toplevel):
      def __init__(self):
          super().__init__()
          self.title("Controls")
          self.geometry("100x300")
          self.configure(background="red")
  
          hidelabels = tk.Button(self, text="Hide the scoreboard", command=forget)
          hidelabels.pack()
  
  
  app = Main()
  ctr = Control()
  
  ctr.mainloop()
  app.mainloop()
  </code></pre>