type Query {
  product: Product
}

type Product  @key(fields: "sku") @extends {
  sku: ID @external
  size: Int @external
  weight: Int @external
  shippingEstimate: String @requires(fields: "size weight")
}

"""
A string-serialized scalar represents a set of fields that's passed to a federated directive, such as @key, @requires, or @provides
"""
scalar _FieldSet