def computescore():
    score = input('what score did you get, sonny?\n')

    try:
        score = float(score)
        if score < 1:
            if score >= 0.9:
                print('A')
            elif score >= 0.8:
                print('B')
            elif score >= 0.7:
                print('C')
            elif score >= 0.6:
                print('D')
            elif score < 0.6:
                print('F')
        else :
            print('you foolclown, only digits between 1 and 0 are valid here')
    except:
        print('enter a number dumbass')

computescore()
