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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 phone_number(self, phone_number):
 """ Sets the phone_number of this OrderFulfillmentRecipient. The phone number of the fulfillment recipient. If provided, overrides the value from customer profile indicated by customer_id. :param phone_number: The phone_number of this OrderFulfillmentRecipient. :type: str """


        if phone_number is None:
            raise ValueError("Invalid value for `phone_number`, must not be `None`")
        if len(phone_number) > 16:
            raise ValueError("Invalid value for `phone_number`, length must be less than `16`")

        self._phone_number = phone_number