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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 order(self, order):
 """ Sets the order of this EnrollmentIdentities. :param order: The order of this EnrollmentIdentities. :type: str """

        if order is None:
            raise ValueError("Invalid value for `order`, must not be `None`")
        allowed_values = ["ASC", "DESC"]
        if order not in allowed_values:
            raise ValueError(
                "Invalid value for `order` ({0}), must be one of {1}"
                .format(order, allowed_values)
            )

        self._order = order