grade = float(input("Enter your grade: "))
if 89 < grade < 101:
print("A")
elif 86 < grade < 90:
print("B+")
elif 79 < grade < 87:
print("B")
elif 76< grade < 80:
print("C+")
elif 69 < grade < 77:
print("C")
elif 66 < grade < 70:
print("D+")
elif 59 < grade < 67:
print("D")
elif -1 < grade < 60:
print("F")
else:
print("Z")
I hope this helps!