def render(self, *args, **kwargs):
    add_item_url = self.get_add_item_url()
    if (add_item_url is not None):
        self.attrs[self._data_add_url_attr] = add_item_url
    return super(DynamicSelectWidget, self).render(*args, **kwargs)
def render(self, *args, **kwargs):
    add_item_url = self.get_add_item_url()
    if (add_item_url is not None):
        self.attrs[self._data_add_url_attr] = add_item_url
    return super(DynamicSelectWidget, self).render(*args, **kwargs)