title: Taking input from user and returning an answer in TKinter
body: <p>This is my first question here so sorry for any mistakes :S.</p>
  
  <p>I have recently picked up python, and I have made some very simple text based application. Now I tried to make one with a proper GUI. I have the code bellow. I have made the GUI, and it's working fine. Apart of a little mistake.</p>
  
  <p>The idea is that the user enters a number and the app will return a Fibonacci number that lies at the same position in the sequence as specified by the user. But when I try it out, all that is shown is the number the user put in, not the Fibonacci number. </p>
  
  <pre><code> ##!/usr/bin/env python
  
  import Tkinter as Tk
  
  class App(object):
      def __init__(self):
          self.root = Tk.Tk()
          self.root.wm_title("Fibonacci Calculator")  
          self.root.wm_iconbitmap("@icon2.xbm")   
          self.label = Tk.Label(self.root, text="Set the digit number you want.")
          self.label.pack()
          self.digits = Tk.StringVar()
          Tk.Entry(self.root, textvariable=self.digits).pack()
  
          self.buttontext = Tk.StringVar()
          self.buttontext.set("Calculate")
          Tk.Button(self.root,
                    textvariable=self.buttontext,
                    command=self.clicked1).pack()
  
          def fibonacci(n):
              a = 0
              b = 1
  
              temp = a
              a = b
              b = temp + b
  
          text_display = fibonacci(self.digits)
          self.label = Tk.Label(self.root, text=text_display)
          self.label.pack()
  
          self.root.mainloop()
  
      def clicked1(self):
          digits = self.digits.get()
          self.label.configure(text=digits)
  
      def button_click(self, e):
          pass
  
  App()
  </code></pre>
  
  <p>I know the script to calculate the Fibonacci numbers works because I tested it separately.</p>
  
  <p>Is it something to do with TKinter?</p>
  
  <p>Thanks for any help :)</p>