Sample
Programmatically generate classes, resolve string forward-reference type annotations, introspect fields, and enforce attribute-level immutability in attrs 26.1.0
sha256:ea93dd9601fe1fb4d4cc69b1d1c649e3133c54d0a3ece0a5f1ef9912bb9b343d
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Execution evidence
Declared environment and signed verification runs are separated so you can see exactly what this sample proves.
Evidence basisSigned contract pass
Verification receipts1
Verification levelL3_CONTRACT_PASS
Declared environment
- Execution context
- python
- Operating system
- linux
- Architecture
- x64
- Runtime
- python
- Language
- python
- Package manager
- pip
Verification-run environments
- Execution context
- python 3.12
- Operating system
- linux alpine · musl
- Architecture
- x64
- Runtime
- python 3.12
- Language
- python
- Package manager
- pip
- Execution
- container · docker
CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17
Case
- Goal
- Programmatically generate classes, resolve string forward-reference type annotations, introspect fields, and enforce attribute-level immutability in attrs 26.1.0 HOW
- Packages
-
attrs 26.1.0
- Environment
- python
- Created
- 2026-08-17T13:04:07Z
Contract
- attrs.resolve_types evaluates string forward references on attrs classes into resolved Python types in place on Attribute.type, while raising NotAnAttrsClassError on non-attrs classes
- assert attrs.make_class dynamically constructs slotted, frozen, and validated attrs classes with full field definition support
- assert attrs.fields_dict requires a class and raises TypeError on instances, whereas attrs.fields accepts both classes and instances
- assert attrs.has returns True for attrs classes and instances and False for standard Python objects
- assert on_setattr=setters.frozen raises FrozenAttributeError on field mutation while @frozen raises FrozenInstanceError
- assert attrs.validate manually re-evaluates all field validators against current instance state on demand
- assert attrs.astuple recursively serializes nested attrs instances and supports attribute filtering via attrs.filters.exclude
- assert initialization lifecycle sequence executes __attrs_pre_init__, converters, validators with converted values, and __attrs_post_init__ deterministically
Files
- NOTES.md
- csx.json
- requirements.txt
- src/__init__.py
- src/models.py
- test/__init__.py
- test/contract.py
Download the source artifact (tar.gz)
Origin Seeder
csx-seed
Verification receipts
- python 3.12 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17 · ed25519:d91480838ac982c9