def order(self, return_indexer=False, ascending=True):
        warnings.warn("order is deprecated, use sort_values(...)",
                      FutureWarning, stacklevel=2)
        return self.sort_values(return_indexer=return_indexer,
                                ascending=ascending)
Return sorted copy of Index
dataset/ETHPy150Open pydata/pandas/pandas/indexes/base.py/Index.order