BSK-E0027 error

Duplicate TypeVar in a Generic... base

Each type parameter in GenericT1, T2, ... must be unique. GenericT, T is an error per PEP 484.

Real basilisk check output

What you see when BSK-E0027 fires on a minimal example:

How to handle it

Every rule is on by default — strict is the default, not a cage. You can dial BSK-E0027 down per-file or per-path from your editor or pyproject.toml, or fix the code so it type-checks. See the Type Safety rules and the complete diagnostic reference.

Canonical URL: https://www.basilisk-python.dev/errors/BSK-E0027