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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 _get_closest_week(self, metric_date):
 """ Gets the closest monday to the date provided. """

        #find the offset to the closest monday
        days_after_monday = metric_date.isoweekday() - 1

        return metric_date - datetime.timedelta(days=days_after_monday)