bpo-40376: slightly improved the wording for os.getgrouplist (GH-19702)

The documentation for os.getgrouplist potentially read like it
returned all groups a user belongs to but it potentially doesn't.

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index 60eac2f78572ed12d4152482b83798acecc499b9..254d6e192cdf08c2886b151031c7b2962fcc4ab3 100644 (file)
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -355,7 +355,8 @@ process and user.
 
    Return list of group ids that *user* belongs to. If *group* is not in the
    list, it is included; typically, *group* is specified as the group ID
-   field from the password record for *user*.
+   field from the password record for *user*, because that group ID will
+   otherwise be potentially omitted.
 
    .. availability:: Unix.