Various sudo-related tips & tricks; these should go into /etc/sudoers or /etc/sudoers.d/ 

# Allow all members of sudo group to execute any command w/out password prompt
%sudo ALL=NOPASSWD: ALL

# Allow one user to execute any command w/o password prompt
sjain ALL=NOPASSWD: ALL

# Allow user to execute only 1 program as root
sjain ALL=(ALL) NOPASSWD: /usr/bin/whatever

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