Your program should include appropriate comments. $(50$ points$)$ Write a program that maintains a list of movies and lets the user to view all the movies in the list, add a movie to the list, or delete a movie from the list. The program should display the following menu:

COMMAND MENU

list $-$ Display all movies

add $-$ Add a movie

del $-$ Delete a movie

exit $-$ Exit program

If the user enters list, the program should display all the movies in the list. If the user enters add, the program should ask for the name of the movie then adds it to the list. If the user enters del, the program should ask for the movie number then delete the movie from the list. Repeat the program until the user chooses the exit command.

Use a list to store the movies and provide at least three starting movie titles. Be sure to divide your program into functions that perform each major task.

Input Validation: If the user selects a command not on the menu, display an error message and let the user to enter another command. Do not use global variables.