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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 describe_addresses(self, *addresses):
 """ List the elastic IPs allocated in this account. @param addresses: if specified, the addresses to get information about. @return: a C{list} of (address, instance_id). If the elastic IP is not associated currently, C{instance_id} will be C{None}. """

        address_set = {}
        for pos, address in enumerate(addresses):
            address_set["PublicIp.%d" % (pos + 1)] = address
        query = self.query_factory(
            action="DescribeAddresses", creds=self.creds,
            endpoint=self.endpoint, other_params=address_set)
        d = query.submit()
        return d.addCallback(self.parser.describe_addresses)