title: Python 2.7 TypeError: unsupported operand type(s) for %: 'NoneType' and 'tuple
body: <p>I've produced the following bit of code for python but for some reason I can't work out why it's returning the error:</p>
  
  <p><code>TypeError: unsupported operand type(s) for %: 'NoneType' and 'tuple</code></p>
  
  <p>I've had a look under  but I can't see what I'm doing wrong :S</p>
  
  <pre><code>temp_appended_data = []
  
  def runme():
      global temp_appended_data
  
      def test():
          return "testdata"
  
      def no():
          return "22453.32214"
  
      def time():
          return "22:12"
  
      def name():
          return "george"
  
      temp_appended_data.append("""test example &lt;br&gt;
                                  Test: % &lt;br&gt;
                                  no: % &lt;br&gt; 
                                  time: % &lt;br&gt;
                                  name: % &lt;br&gt;
                                  """) % (test(),no(),time(),name())
  
      print temp_appended_data
  
  runme()
  </code></pre>
  
  <p>Anyone able to see and fix what I've done wrong?</p>
  
  <p>Thanks
  - Hyflex</p>