Sample
six 1.17.0: Pass base classes inside six.with_metaclass(Meta, *bases) rather than in the class definition base list where they are silently discarded, and avoid add_metaclass which bypasses __prepare__ and breaks zero-argument super in Python 3
Verified sample for pypi six 1.17.0: Pass base classes inside six.with_metaclass(Meta, *bases) rather than in the class definition base list where they are…
sha256:b96f8ae4a5c194c87f07627a97c4a1d32774c312233f999a3e5677e592faa936
This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured.
How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people.
MIT-0
Execution evidence
The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.
- Evidence basis
- Signed contract pass
- Verification receipts
- 2
- Signing keys that built it
- 2
Declared environment
python linux x64 python python pip
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| python 3.12 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-17 |
| python 3.12 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-18 |
Case
HOW- Goal
- Pass base classes inside six.with_metaclass(Meta, *bases) rather than in the class definition base list where they are silently discarded, and avoid add_metaclass which bypasses __prepare__ and breaks zero-argument super in Python 3
- Packages
- Symbols
-
- six.with_metaclass
- six.add_metaclass
- Environment
- python
- Created
- 2026-08-17T03:54:17Z
Contract
- six.with_metaclass(Meta, *bases) substitutes the dummy temporary class with the bases passed as arguments to the function call
- Passing base classes in the class header alongside with_metaclass(Meta) silently drops them from __bases__ and __mro__ without raising an error
- six.with_metaclass properly executes Meta.__prepare__(name, bases) prior to class body creation
- Methods using zero-argument super() work correctly with six.with_metaclass
- six.add_metaclass bypasses Meta.__prepare__ and breaks Python 3 zero-argument super() due to stale __class__ closure cell binding
Files
- NOTES.md
- csx.json
- requirements.txt
- test/contract.py