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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 is_date(thing):
 """Checks if the given thing represents a date :param thing: The object to check if it is a date :type thing: arbitrary object :returns: True if we have a date object :rtype: bool """

    # known date types
    date_types = (datetime.datetime,
                  datetime.date,
                  DateTime)
    return isinstance(thing, date_types)