title: Python 2.7 Tkinter - Determine which Radiobutton has been selected
body: <p>Assuming the following code has been written:</p>
  <pre><code>self.firstRadioButton = Radiobutton(self.__canvas, text=&quot;ONE&quot;, fg='white', bg=BACKGROUND_COLOR, variable=self.selectedONE, value=1)
  
  self.secondRadioButton = Radiobutton(self.__canvas, text=&quot;TWO&quot;, fg='white', bg=BACKGROUND_COLOR, variable=self.selectedTWO, value=2)
  </code></pre>
  <p>I am trying to determine which radio button has been selected and then extract the value of whichever one the user picks. How do I do this?</p>