title: Update LCD Number countdown
body: <p>I'm very new to Python and I have made a very simple countdown timer. The GUI was created in Qt Designer. There is a spin box for input of seconds, a start button and an LCD number counter. The counter counts down fine using the code below:</p>
  
  <pre><code>     def start_btn_clicked(self):
           x = self.Minute_spinBox.value()
           for i in xrange(x,0,-1):
               time.sleep(1)
               print (i)
  </code></pre>
  
  <p>So that I could see what was happening as I played around with it, I added the print instruction so that it shows the countdown in the Python console as it runs. I then thought I could maybe quite easily have the LCD number display the countdown with something like:</p>
  
  <pre><code>    self.lcdNumber.display(i)("%SS")
  </code></pre>
  
  <p>But no matter what I try, I cant get it to show. With the line above, I get the first number displayed, but then I get an error saying:</p>
  
  <pre><code>    self.lcdNumber.display(i)("%SS")
      TypeError: 'NoneType' object is not callable
  </code></pre>
  
  <p>I have tried so many variations that I no longer know where I started and here was me thinking it would be simple. I'd love to know why I cant get it to display the countdown. </p>