    # File lib/fog/aws/requests/emr/add_instance_groups.rb, line 23
            def add_instance_groups(job_flow_id, options={})

              if instance_groups = options.delete('InstanceGroups')
                options.merge!(Fog::AWS.indexed_param('InstanceGroups.member.%d', [*instance_groups]))
              end

              request({
                'Action'  => 'AddInstanceGroups',
                'JobFlowId' => job_flow_id,
                :parser   => Fog::Parsers::AWS::EMR::AddInstanceGroups.new,
              }.merge(options))
            end