Why do you have argument :id, types.ID in ProductInput <GraphQL::InputObjectType>? Is ID writable, editable?

[ghost]

I'm wondering why you have argument :id, types.ID in ProductInput <GraphQL::InputObjectType>, here: https://github.com/tb/northwind-graphql-ruby/blob/master/app/graphql/types/product_type.rb.

Is ID writable, editable?

Types::ProductInputType = GraphQL::InputObjectType.define do
  name "ProductInput"

  argument :id, types.ID
  argument :product_name, types.String
  argument :image_url, types.String
  argument :list_price, types.String
  argument :category, types.String
  argument :supplier_id, types.ID
  argument :supplier, Types::SupplierInputType
end

[ghost]

I'm sorry. My mistake.