  
  
  class TestChoiceFieldChoicesValidate(TestCase):
      CHOICES = [
          (0, 'Small'),
          (1, 'Medium'),
          (2, 'Large'),
 
</s> remove         # Allow either single or paired choices style:
        # choices = [1, 2, 3]
        # choices = [(1, 'First'), (2, 'Second'), (3, 'Third')]
        pairs = [
            isinstance(item, (list, tuple)) and len(item) == 2
            for item in choices
        ]
        if all(pairs):
            self.choices = OrderedDict([(key, display_value) for key, display_value in choices])
        else:
            self.choices = OrderedDict([(item, item) for item in choices])
 </s> add         flat_choices = [self.flatten_choice(c) for c in choices]
        self.choices = OrderedDict(itertools.chain(*flat_choices))
# regression tests for issue: 1533

  
  
# regression tests for issue: 1533

  class TestChoiceFieldChoicesValidate(TestCase):
      CHOICES = [
          (0, 'Small'),
          (1, 'Medium'),
          (2, 'Large'),
keep add keep keep keep keep keep
 Add support for grouped choices.

This also adds support for mixing single and paired choices:
```
[
    ('poor', 'Poor quality'),
    'medium',
    ('good', 'Good quality'),
]
``` 
tests/test_validation.py