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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 drawdown_end(self, return_date=False):
 """The date of the drawdown trough. Date at which the drawdown was most negative. Parameters return_date : bool, default False If True, return a `datetime.date` object. If False, return a Pandas Timestamp object. Returns ------- datetime.date or pandas._libs.tslib.Timestamp """


        end = self.drawdown_idx().idxmin()
        if return_date:
            return end.date()
        return end