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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 on(self, year, month, day):
 """ Returns a new instance with the current date set to a different date. :param year: The year :type year: int :param month: The month :type month: int :param day: The day :type day: int :rtype: DateTime """

        return self.set(year=int(year), month=int(month), day=int(day))