Update user name.
First i will show the all users in the system using the command
Then the i am going to change user name "thamilnadu" to "bangalore" using the command "sudo usermod -l new_user_name old_user_name".
Next i am going to display the changed user name.
Update the group name.
First i will show all the groups in the sysytem using the command "cat /etc/group".
Then i am going to change the group name "my_india" to "india" using the command "sudo groupmod -n new_group_name old_group_name".
Next i am going to display the changed group name