Strange phenomenon on python-fu on Mac OS

Hi,
On python-fu in GIMP 3.04 +Mac OS 15.6 ARM Japanese version, I encountered strange phenomenon. I tried to get environment variable about language.

When I started GIMP in normal mode, the result of os.getenv(“LANG”) was None. However in verbose mode, the result is “ja-JP.UTF-8”.

Is this difference is intended or bug?