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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def min_date(self, symbol):
 """ Return the minimum datetime stored for a particular symbol Parameters symbol : `str` symbol name for the item """

        res = self._collection.find_one({SYMBOL: symbol}, projection={ID: 0, START: 1},
                                        sort=[(START, pymongo.ASCENDING)])
        if res is None:
            raise NoDataFoundException("No Data found for {}".format(symbol))
        return utc_dt_to_local_dt(res[START])