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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 associate_route_table(self, route_table_id, subnet_id):
 """ Associates a route table with a specific subnet. :type route_table_id: str :param route_table_id: The ID of the route table to associate. :type subnet_id: str :param subnet_id: The ID of the subnet to associate with. :rtype: str :return: The ID of the association created """

        params = {
            'RouteTableId': route_table_id,
            'SubnetId': subnet_id
        }

        result = self.get_object('AssociateRouteTable', params, ResultSet)
        return result.associationId