False-positive 'unused-import' for base class name used in type annotation

[saf]

Starting from pylint 2.4.0, an imported symbol from my own package which is only used in a # type: annotation has been unexpectedly reported as an unused-import.

This works fine with pylint 2.3.1.

Steps to reproduce

mod1/my_types.py:

class Base():
    pass

class Foo(Base):
    pass

class Bar(Base):
    pass

mod1/usage.py:

#!/usr/bin/python3

import sys

from mod1.my_types import Base, Foo, Bar

def main():
    if sys.argv[1:]:
        foo_or_bar = Foo()  # type: Base
    else:
        foo_or_bar = Bar()

    print(foo_or_bar.__class__)


if __name__ == "__main__":
    main()

Current behavior

mod1/usage.py:5: [W0611: unused-import] Unused Base imported from mod1.my_types

Expected behavior

No error reported about the unused import.

pylint --version output

$ python3 -m pylint --version
pylint 2.4.2
astroid 2.3.1
Python 3.6.8 (default, Oct  7 2019, 12:59:55) 
[GCC 8.3.0]

[PCManticore]

Thanks, I can reproduce the issue.