    # File lib/fog/aws/requests/rds/add_tags_to_resource.rb, line 29
            def add_tags_to_resource(rds_id, tags)
              response = Excon::Response.new
              if server = self.data[:servers][rds_id]
                self.data[:tags][rds_id].merge! tags
                response.status = 200
                response.body = {
                  "ResponseMetadata"=>{ "RequestId"=> Fog::AWS::Mock.request_id }
                }
                response
              else
                raise Fog::AWS::RDS::NotFound.new("DBInstance #{rds_id} not found")
              end
            end