This module provides access to the Unix group database.
It is available on all Unix versions.
Group database entries are reported as 4-tuples containing the
following items from the group database (see <grp.h>), in order:
the name of the group
the (encrypted) group password; often empty
the numerical group ID
all the group member's user names
The gid is an integer, name and password are strings, and the member
list is a list of strings.
(Note that most users are not explicitly listed as members of the
group they are in according to the password database. Check both
databases to get complete membership information.)