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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 cancel_global_ip(self, global_ip_id):
 """Cancels the specified global IP address. :param int id: The ID of the global IP to be cancelled. """

        service = self.client['Network_Subnet_IpAddress_Global']
        ip_address = service.getObject(id=global_ip_id, mask='billingItem')
        billing_id = ip_address['billingItem']['id']

        return self.client['Billing_Item'].cancelService(id=billing_id)