def add_callback(self, cb):
        self._callbacks.append(cb)
>>> d = OrderedDict(((1, 3), (3, 2), (2, 1)))
dataset/ETHPy150Open glue-viz/glue/glue/viewers/custom/qt/custom_viewer.py/FormElement.add_callback--crossover with--dataset/ETHPy150Open editorconfig/editorconfig-vim/plugin/editorconfig-core-py/editorconfig/odict.py/OrderedDict.setdefault