Get a pack

{  "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08",  "shop_id": "string",  "name": "string",  "mode": "fixed",  "base_product_id": "string",  "base_variant_id": "string",  "eligible_product_ids": [    "string"  ],  "eligible": [    {      "product_id": "string",      "variant_id": "string",      "title": "string",      "image_url": "string",      "price_each": "string"    }  ],  "tiers": [    {      "size": 1,      "pack_price": 1,      "shopify_product_id": "string",      "shopify_variant_id": "string",      "shopify_handle": "string"    }  ],  "status": "draft",  "created_at": "2019-08-24T14:15:22Z",  "updated_at": "2019-08-24T14:15:22Z"}