$ curl cheat.sh/
# groups
# Print group memberships for a user.
# See also: `groupadd`, `groupdel`, `groupmod`.
# More information: <https://www.gnu.org/software/coreutils/groups>.

# Print group memberships for the current user:
groups

# Print group memberships for a list of users:
groups username1 username2 ...

$
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