title: My Gui doesn't show output text after clicking button
body: <p>here is a newbie with Python. 
  I'm programming this simple GUI:</p>
  
  <pre><code>from Tkinter import *
  
  root = Tk()
  
  def print_name():
     return  'Here is Steve'
  
  here_goes_text = print_name()
  
  button = Button(root,text='Say hello',command = print_name)
  button.pack()
  text = Text(root)
  text.insert(END,here_goes_text)
  text.pack()
  
  root.mainloop()
  </code></pre>
  
  <p>What I wish is that after I click the "Say hello" button the Gui show me "Hi I'm Steve" on the text widget below.
  Unfortunately right now when I run the program it show me immediately "Hi I'm Steve" on the text below and if I click the "Say hello" button nothing happens.</p>
  
  <p>What am I doing wrong?</p>