{
  "context": "Evaluates whether the solution uses aenum's NamedConstant/Constant to build immutable payment status constants with built-in name/value metadata, by-value lookups, and ordered iteration. Checks focus on leveraging aenum primitives instead of hand-rolled dictionaries or ad hoc immutability guards.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "Uses NamedConstant",
      "description": "PaymentStatus is declared as a subclass of aenum.NamedConstant or aenum.Constant, not a plain class or Enum, ensuring the library's constant behaviors are active.",
      "max_score": 25
    },
    {
      "name": "Built-in lookup",
      "description": "status_from_code delegates to aenum's by-value resolution (e.g., PaymentStatus(code) or accessing value-to-member maps) rather than maintaining a separate manual dictionary, and raises ValueError for unknown codes.",
      "max_score": 25
    },
    {
      "name": "Immutability guard",
      "description": "Relies on NamedConstant/Constant's prevention of attribute rebinding or deletion (AttributeError on set/del) instead of custom setter overrides or defensive copies.",
      "max_score": 20
    },
    {
      "name": "Name/value usage",
      "description": "Retrieves status metadata via the NamedConstant member interfaces (name/value attributes) rather than duplicating labels or codes in parallel structures.",
      "max_score": 15
    },
    {
      "name": "Library iteration",
      "description": "list_status_codes derives ordering from NamedConstant's member iteration (e.g., list(PaymentStatus) or PaymentStatus.__members__.items()) instead of hardcoded lists.",
      "max_score": 15
    }
  ]
}