def toggle_checkmark(self, thread_id, item, checked=True):
        if checked:
            item.attrib["class"] = "checked"
        else:
            item.attrib["class"] = ""
        return self.edit_document(thread_id=thread_id,
                                  content=xml.etree.cElementTree.tostring(item),
                                  section_id=item.attrib["id"],
                                  operation=self.REPLACE_SECTION)
Sets the checked state of the given list item to the given state.
dataset/ETHPy150Open quip/quip-api/python/quip.py/QuipClient.toggle_checkmark