["A" for x in scores if x >=80] + ["B" for x in scores if 60<=x<80] + ["C" for x in scores if x<60]

["A" if x >= 80 else "B" if x >= 60 else "C" for x in scores]

[x >=80 ? "A" : x >=60 ? "B" : "C" for x in scores]

{ "A" if x >=80 else "B" if x >=60 else "C" for x in scores }