# File lib/aws/emr/instance_group_collection.rb, line 48
      def create role, instance_type, instance_count, options = {}

        options[:instance_role] = role
        options[:instance_type] = instance_type
        options[:instance_count] = instance_count
        options[:bid_price] = options[:bid_price].to_s if options[:bid_price]

        client_opts = {}
        client_opts[:job_flow_id] = job_flow.job_flow_id
        client_opts[:instance_groups] = [options]

        resp = client.add_instance_groups(client_opts)

        self[resp.data[:instance_group_ids].first]

      end