title: python: cannot concatenate 'str' and 'long' objects
body: <p>I'm trying to set up a choice field in django, but I don't think this is a django issue. The choices field takes an iterable (e.g., a list or tuple) of 2-tuples to use as choices for this field.</p>
  
  <p>Here's my code:</p>
  
  <pre><code>self.fields['question_' + question.id] = forms.ChoiceField(
                  label=question.label,
                  help_text=question.description,
                  required=question.answer_set.required,
                  choices=[("fe", "a feat"), ("faaa", "sfwerwer")])
  </code></pre>
  
  <p>for some reason, i always get the following error:</p>
  
  <pre><code>TypeError - cannot concatenate 'str' and 'long' objects
  </code></pre>
  
  <p>The last line is always highlighted.</p>
  
  <p>I'm not trying to concatenate anything. Almost regardless of what I change the list to for the 'choices' parameter, I get this error.</p>
  
  <p>What's going on?</p>