title: My model field gives me Value u'0' is not a valid choice error?
body: <pre><code>FOOBAR = (
      (0, 'foo'),
      (1, 'bar'),
  )
  
  class Foobaz(models.Model):
      type = models.CharField(max_length=1, choices=FOOBAR, \
                                         verbose_name=_('foobar type'))
  
  class FoobazForm(forms.ModelForm):
      class Meta:
      model = Foobaz
          fields = ('type')
  </code></pre>
  
  <p>In views <code>foo_form = FoobazForm(request.POST)</code>
  When I do <code>foo_form.is_valid()</code> It gives me validation error <code>u'0' is not a valid choice</code>.
  Where I am doing something wrong?</p>