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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_security_groups(self, *names):
 """Describe security groups. @param names: Optionally, a list of security group names to describe. Defaults to all security groups in the account. @return: A C{Deferred} that will fire with a list of L{SecurityGroup}s retrieved from the cloud. """

        group_names = {}
        if names:
            group_names = dict([("GroupName.%d" % (i + 1), name)
                                for i, name in enumerate(names)])
        query = self.query_factory(
            action="DescribeSecurityGroups", creds=self.creds,
            endpoint=self.endpoint, other_params=group_names)
        d = query.submit()
        return d.addCallback(self.parser.describe_security_groups)