complete suggestion to separate available_releases

from available package sets

src/mpsd_software_manager/mpsd_software.py

@@ -471,7 +471,7 @@ def set_up_logging(loglevel="warning", file_path=None):
     )
 
 
-def get_available_package_sets(mpsd_release: Union[str, None]) -> List[str]:
+def get_available_package_sets(mpsd_release: str) -> List[str]:
     """Given a release, return the available package_sets.
 
     This is based on the spack-environment's repository [1]. For this function
@@ -480,8 +480,6 @@ def get_available_package_sets(mpsd_release: Union[str, None]) -> List[str]:
     We use a temporary directory to clone the repository locally, which is
     deleted upon successful completion of the function.
 
-    If `mpsd_release` is None, display the available release versions, and exit.
-
     [1] https://gitlab.gwdg.de/mpsd-cs/spack-environments.git
 
     Returns
@@ -504,14 +502,6 @@ def get_available_package_sets(mpsd_release: Union[str, None]) -> List[str]:
     logging.debug(f"get_available_package_sets({mpsd_release=})")
     print_log = logging.getLogger("print")
 
-    # display available releases if no release is specified:
-    if mpsd_release is None:
-        releases = get_available_releases()
-        print("Available MPSD software releases:")
-        for release in releases:
-            print(f"    {release}")
-        sys.exit(0)
-
     logging.info(f"Retrieving available package_sets for release {mpsd_release}")
 
     # create temporary directory
@@ -806,13 +796,12 @@ def get_available_releases(print_result: bool = False) -> List[str]:
     releases = ["dev-23a"]
     print_log = logging.getLogger("print")
     if print_result:
-        print_log("Available MPSD software releases:")
+        print_log.info("Available MPSD software releases:")
         for release in releases:
-            print(f"    {release}")
+            print_log.info(f"    {release}")
     return releases
 
 
-
 def get_release_info(mpsd_release: str, root_dir: Path) -> Tuple[str, str, List[str]]:
     """
     Get information about the specified release.
@@ -1457,7 +1446,11 @@ def main():
     elif args.action == "prepare":
         prepare_environment(args.release, root_dir)
     elif args.action == "available":
-        get_available_package_sets(args.release)
+        if args.release:
+            get_available_package_sets(args.release)
+        else:
+            get_available_releases(print_result=True)
+            sys.exit(0)
     else:
         message = (
             f"No known action found ({args.action=}). Should probably never happen."