grade.py

score = int(input("Enter your score: "))

print("Your score is: ")

# improvement
if score >= 90:
    print("A")
elif score >= 80:
    print("B")
elif score >= 70:
    print("C")
elif score >= 60:
    print("D")
else:
    print("F")

# improvement
if 90 <= score <= 100:
    print("A")
elif 80 <= score <= 90:
    print("B")
elif 70 <= score <= 80:
    print("C")
elif 60 <= score <= 70:
    print("D")
else:
    print("F")

if score >= 90 and score <= 100:
    print("A")
elif score >= 80 and score <= 90:
    print("B")
elif score >= 70 and score <= 80:
    print("C")
elif score >= 60 and score <= 70:
    print("D")
else:
    print("F")