class Lab6AQ2:
    @staticmethod
    def main():
        while True:
            testSC = input("Enter Test Score: ")

            # check if letters and/or special characters were entered for test score
            if not testSC.isdigit():
                print("Invalid test score. Unknown character(s) detected!!!!")
            # check if numbers less than 0 or greater than 100 were entered for test score     
            elif int(testSC) < 0 or int(testSC) > 100:
                print("Invalid test score. Number outside of grading scale detected!!!!")
            # check if numbers from 90 to 100 were entered for test score    
            elif int(testSC) >= 90 and int(testSC) <= 100:
                print("Student received an A!!!!")
                print("Student passed the test!!!!")
            # check if numbers from 80 to 89 were entered for test score    
            elif int(testSC) >= 80 and int(testSC) <= 89:
                print("Student received an B!!!!")
                print("Student passed the test!!!!")
            # check if numbers from 70 to 79 were entered for test score
            elif int(testSC) >= 70 and int(testSC) <= 79:
                print("Student received an C!!!!")
                print("Student passed the test!!!!")
            # check if numbers from 60 to 69 were entered for test score
            elif int(testSC) >= 60 and int(testSC) <= 69:
                print("Student received an D!!!!")
                print("Student passed the test!!!!")
            # check if numbers from 50 to 59 were entered for test score
            elif int(testSC) >= 50 and int(testSC) <= 59:
                print("Student received an E!!!!")
                print("Student passed the test!!!!")
            # otherwise numbers from 0 to 49 were entered for test score
            else:
                print("Student received an F!!!!")
                print("Student failed the test!!!!")
            
            resp = input("Do you want to process another test score?: ")

            # check if user wants to enter another test score
            if resp == "yes":
                print("Processing another test score!!!!")
                continue # go back to start of program
            # check if user does not want to enter another test score
            elif resp == "no":
                print("Goodbye!!!!")
                break # exit program
            # otherwise the user entered unexpected characters
            else:
                print("Unexpected error. Exiting program!!!!")
                break # exit program

Lab6AQ2.main()