Django - populate a MultipleChoiceField via request.user.somechoice_set.all()

Is there a more efficient, or cleaner way to do the following?

class SpamForm(ModelForm):
    some_choices = fields.MultipleChoiceField()

    def __init__(self, *args, **kwargs):
        super(SpamForm, self).__init__(*args, **kwargs)
        self.fields['some_choices'].choices = [[choice.pk, choice.description] for choice in self.instance.user.somechoice_set.all()]

    class Meta:
        model = Spam

This is to populate the new form with choices that pertain to the current request.user (which is set on the instance that's passed into the form). Is t开发者_如何学Gohere a better way?

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Use a ModelMultipleChoiceField in the form and set its queryset in __init__().