Write a program that given a list of letter grades associated with a student, flags the student as scholarship$-$eligible if the student has $3$ or more times the grade of A in the list.

The program should use a function named "flag$\_$for$\_$scholarship" that receives a single list of grade letters $($A$,$ A$-,$ B$+,$ B$,$ B$-,$ C$+,$ C$,$ D$,$ F$)$ as input, and returns a single Boolean value $($True or False$)$ as output, specifically: True, if the student has $3$ or more times the grade letter A; False otherwise.

Test your program over multiple and different students $($letter grade lists$).$

Example:

$[$A$,$ B$,$ C$,$ B$-,$ B$+,$ A$,$ A$]$ True

$[$B$-,$ B$,$ A$,$ C$,$ C$+,$ A$,$ C$]$ False