'A hook for adding extra fields on to each form instance.'

def add_fields(self, form, index):

    if self.can_order:
        if ((index is not None) and (index < self.initial_form_count())):
            form.fields[ORDERING_FIELD_NAME] = IntegerField(label=_(u'Order'), initial=(index + 1), required=False)
        else:
            form.fields[ORDERING_FIELD_NAME] = IntegerField(label=_(u'Order'), required=False)
    if self.can_delete:
        form.fields[DELETION_FIELD_NAME] = BooleanField(label=_(u'Delete'), required=False)
