code: def closest(self, dt1, dt2):
          
          dt1 = self.__class__(dt1.year, dt1.month, dt1.day)
          dt2 = self.__class__(dt2.year, dt2.month, dt2.day)
  
          if self.diff(dt1).in_seconds() < self.diff(dt2).in_seconds():
              return dt1
  
          return dt2
docs: Get the closest date from the instance.
  
          :type dt1: Date or date
          :type dt2: Date or date
  
          :rtype: Date