How to classify local folders as first party modules except venv

Let's say that my project has a structure as such:

root
--package1
----module1
------submodule1
----module2
--package2
----module1
----module2
--venv

I could import every single module starting from root, like from root.package1.module1.submodule1 import function, but I feel like when importing into package1.module2, the prettier way of doing so would be from module1.submodule1 import function, but then it's recognized as third party module. I've tried adding this to pyproject.toml
[tool.isort] src_paths=['root'] virtual_env=['venv']
or
[tool.isort] src_paths=['root'] known_third_party=['venv']
but both of them seem to ignore venv and classify every third and first party modules into the same group.
How do I go around this?

Start by reviewing the [tool.isort] configuration examples in the issue, especially src_paths, virtual_env, and known_third_party, then trace how isort classifies imports from the shown project structure. Done would mean a documented or tested configuration that separates local modules from third-party imports while excluding venv.