cli: add 'config init' command

my/core/init.py

@@ -24,26 +24,13 @@ def assign_module(parent: str, name: str, module: ModuleType) -> None:
 del ModuleType
 
 
-def get_mycfg_dir():
-    import appdirs # type: ignore[import]
-    from pathlib import Path
-    import os
-    # not sure if that's necessary, i.e. could rely on PYTHONPATH instead
-    # on the other hand, by using MY_CONFIG we are guaranteed to load it from the desired path?
-    mvar = os.environ.get('MY_CONFIG')
-    if mvar is not None:
-        mycfg_dir = Path(mvar)
-    else:
-        mycfg_dir = Path(appdirs.user_config_dir('my'))
-    return mycfg_dir
-
-
 # separate function to present namespace pollution
 def setup_config() -> None:
     import sys
     import warnings
     from typing import Optional
 
+    from .preinit import get_mycfg_dir
     mycfg_dir = get_mycfg_dir()
 
     if not mycfg_dir.exists():