def max_date(self, symbol):
        """
        Return the maximum datetime stored for a particular symbol

        Parameters
        ----------
        symbol : `str`
            symbol name for the item
        """
        res = self._collection.find_one({SYMBOL: symbol}, projection={ID: 0, END: 1},
                                        sort=[(START, pymongo.DESCENDING)])
        if res is None:
            raise NoDataFoundException("No Data found for {}".format(symbol))
        return utc_dt_to_local_dt(res[END])
Return the maximum datetime stored for a particular symbol

        Parameters
        ----------
        symbol : `str`
            symbol name for the item