def METHOD_NAME(self, jsonpath):
    '''Update JSON data at jsonpath. Return the data provided'''
    parent, key, data = self.jsonwalk(jsonpath)
    if data is not None:
        data = self.parse_body_as_json()
        parent[key].update(data)
        self.changed = True
    self.write(json.dumps(data, **self.json_kwargs))