How to turn on vlog for a specific file?

The `-v` flag can be used to enable vlog messages across all files, but is it possible to enable only for a specific file(s)? I think the C++ logging library uses `--vmodule` but there's no such flag for Python, even though a comment in the code says it should be possible: https://github.com/abseil/abseil-py/blob/master/absl/logging/__init__.py#L53

(BTW it'd be great to document the `-v` flag somewhere, it took me a while to figure that one out.)