mypy is failing on `from git import Blob`

pbeza

Why mypy is failing when running this code:

$ cat /tmp/test.py 
from git import Blob

$ mypy /tmp/test.py
/tmp/test.py:1: error: Module "git" has no attribute "Blob"
Found 1 error in 1 file (checked 1 source file)

$ python3 -c "import git; print(git.__version__)"
3.1.23

$ mypy --version
mypy 0.910

$ python3 --version
Python 3.9.7

I can see that there is a conditional import in git/objects/base.py:

if TYPE_CHECKING:
    from git.repo import Repo
    from gitdb.base import OStream
    from .tree import Tree
    from .blob import Blob
    from .submodule.base import Submodule
    from git.refs.reference import

and it seems that TYPE_CHECKING is set to False (I guess so based on the above error). Do you know why is that? How to workaround the problem?