2. (3 marks) Write a Linux shell script that finds all files on the entire system that contain a given specific text string (supplied at the script's command line), and changes the permissions of each such file such that only Alice_" has read and execute permissions, where is replaced by your actual full name (e.g., this course's TA would use "AlirezaNamanloo"). Note that your script should handle any error conditions by printing out a descriptive error message to the shell and then exiting. Submit your script with the filename "Lastname_firstname_restrictfiles.sh