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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 add_global_ip(self, version=4, test_order=False):
 """Adds a global IP address to the account. :param int version: Specifies whether this is IPv4 or IPv6 :param bool test_order: If true, this will only verify the order. """

        # This method is here to improve the public interface from a user's
        # perspective since ordering a single global IP through the subnet
        # interface is not intuitive.
        return self.add_subnet('global', version=version,
                               test_order=test_order)