In functools.partial, container of subclass is not recognized as container of baseclass

[RmZeta2718]

Environment data

• Language Server version: v2023.3.10
• OS and version: ubuntu18.04
• Python version (& distribution if applicable, e.g. Anaconda): Anaconda python3.10

Code Snippet

from functools import partial

class BaseClass:
    pass

class SubClass(BaseClass):
    pass

def func(base: BaseClass):
    pass

def func_list(base: list[BaseClass]):
    pass

def func_set(base: set[BaseClass]):
    pass

sub = SubClass()

func(sub)  # works fine
func_list([sub])  # works fine
func_set({sub})  # works fine

partial(func, sub)  # works fine
partial(func_list, [sub])  # error
partial(func_set, {sub})  # error

Expected behavior

No errors reported.

Actual behavior

Argument of type "list[SubClass]" cannot be assigned to parameter "base" of type "list[BaseClass]" in function func_list" Pylance(reportGeneralTypeIssues)

Argument of type "set[SubClass]" cannot be assigned to parameter "base" of type "set[BaseClass]" in function "func_set" Pylance(reportGeneralTypeIssues)

[erictraut]

Thanks for the bug report. This will be addressed in the next release.

[debonte]

This issue has been fixed in prerelease version 2023.3.21, which we've just released. You can find the changelog here: CHANGELOG.md