参考答案是错误的，没有考虑换行符

OpenFile = open("source.txt","r")
lines = OpenFile.readlines()
CreateFile = open("target.txt","w")
for i in lines:
    Ri = i[::-1]
    if lines.index(i) == -1:
        break
    Ri = Ri.strip()
    Ri = Ri+"\n"
    CreateFile.write(Ri)
OpenFile.close()
CreateFile.close()