How to make terminal ask for password every time you type sudo command

when you type sudo command for the first time in a terminal it will ask you the sudo password.
This password will be remembered by that terminal for 15 minutes by default.

If you want terminal to ask for password each time you type sudo command just do as said below.
1. Type at terminal

sudo visudo

2. Edit as shown below

 Change

  Defaults env_reset

 to

  Defaults env_reset,timestamp_timeout=0