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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 get_obj(self, name):
 """ Returns the AWS object associated with a given option. The heuristics used are a bit lame. If the option name contains the word 'bucket' it is assumed to be an S3 bucket, if the name contains the word 'queue' it is assumed to be an SQS queue and if it contains the word 'domain' it is assumed to be a SimpleDB domain. If the option name specified does not exist in the config file or if the AWS object cannot be retrieved this returns None. """

        val = self.get(name)
        if not val:
            return None
        if name.find('queue') >= 0:
            obj = boto.lookup('sqs', val)
            if obj:
                obj.set_message_class(ServiceMessage)
        elif name.find('bucket') >= 0:
            obj = boto.lookup('s3', val)
        elif name.find('domain') >= 0:
            obj = boto.lookup('sdb', val)
        else:
            obj = None
        return obj