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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 employee_id(self, employee_id):
 """ Sets the employee_id of this Shift. The ID of the employee this shift belongs to. :param employee_id: The employee_id of this Shift. :type: str """


        if employee_id is None:
            raise ValueError("Invalid value for `employee_id`, must not be `None`")
        if len(employee_id) < 1:
            raise ValueError("Invalid value for `employee_id`, length must be greater than or equal to `1`")

        self._employee_id = employee_id