PY3.C0131
Typevar double variance
Emitted when both the "covariant" and "contravariant" keyword arguments are set to "True" in a TypeVar.
Noncompliant Code:
Copy
from typing import TypeVar
T = TypeVar("T", covariant=True, contravariant=True)
Compliant Code:
Copy
from typing import TypeVar
T_co = TypeVar("T_co", covariant=True)
T_contra = TypeVar("T_contra", contravariant=True)