Use python to create a program with a function called compute_grade that asks a score as its parameter and returns a grade. Please define the function, then in the main program, please ask to input score, do input validation, call the function to get the result, then output the result.

No loop, no list, no string.

Score Grade

>= 0.9 A

>= 0.8 B

>= 0.7 C

>= 0.6 D

< 0.6 F

Running output examples:

Enter score: 0.95

A

Enter score: perfect

Bad score

Enter score: 10.0

Bad score

Enter score: 0.75

C

Enter score: 0.5

F