{
  "tiers": [
    {
      "total_exp_required": 5,
      "groups": [
        {
          "num_to_select": 2,
          "trades": [
            {
              "wants": [
                {
                  "item": "minecraft:wheat",
                  "quantity": {
                    "min": 18,
                    "max": 22
                  }
                }
              ],
              "gives": [{ "item": "minecraft:emerald" }]
            }
          ]
        }
      ]
    }
  ]
}
