def opt_in_phone_number(phoneNumber=None):
    """
    Use this request to opt in a phone number that is opted out, which enables you to resume sending SMS messages to the number.
    You can opt in a phone number only once every 30 days.
    See also: AWS API Documentation
    
    
    :example: response = client.opt_in_phone_number(
        phoneNumber='string'
    )
    
    
    :type phoneNumber: string
    :param phoneNumber: [REQUIRED]
            The phone number to opt in.
            

    :rtype: dict
    :return: {}
    
    
    """
    pass
