BootstrappedMixin for form - adds Bootstrap3.0 classes & placeholder

BootstrappedMixin

class BootstrappedMixin(object):
    def __init__(self, *args, **kwargs):
        super(BootstrappedMixin, self).__init__(*args, **kwargs)
        for field_name in self.fields:
            field = self.fields.get(field_name)
            attrs = {'class': 'form-control'}
            if field and isinstance(field.widget, forms.TextInput):
                attrs.update({'placeholder': field.label})
            field.widget.attrs = attrs