Question On Validating a Specific Scenario in Postman

Question

I've one scenario that needs to be validated in postman.

Let's consider there's a scenario where we have to verify the list of all product information. Here is the example of response body:

{
  "products": [
    {
      "id": 1,
      "name": "Laptop",
      "brand": "ABC",
      "price": 1200.00,
      "specifications": {
        "processor": "Intel Core i5",
        "RAM": "8GB",
        "storage": "256GB SSD",
        "display": "15.6-inch Full HD"
      },
      "availability": true
    },
    {
      "id": 2,
      "name": "Smartphone",
      "brand": "XYZ",
      "price": 699.99,
      "specifications": {
        "processor": "Snapdragon 855",
        "RAM": "6GB",
        "storage": "128GB",
        "screen_size": "6.2-inch AMOLED"
      },
      "availability": false
    },
    {
      "id": 3,
      "name": "Headphones",
      "brand": "AudioTech",
      "price": 99.99,
      "specifications": {
        "type": "Over-ear",
        "wireless": true,
        "color": "Black"
      },
      "availability": true
    }
  ]
}

For this, I want to verify the name, brand price for that product etc. How can this be done without having to store the expected value in any other external file. I want to make validation for this test dynamic.Let say, if there's any product information added in future, I don't want to manually come and store the expected information in excel or JSON file and then do the validation.Please note that, I don't want to first add the product and then check whether the product details there in the list.