在python中，如何比较两个数字字符串而不将它们转换为int()？

num1 = "123"
num2 = "456"

if num1 == num2:
    print("num1和num2相等")
elif num1 != num2:
    print("num1和num2不相等")
elif num1 > num2:
    print("num1大于num2")
elif num1 < num2:
    print("num1小于num2")
elif num1 >= num2:
    print("num1大于等于num2")
elif num1 <= num2:
    print("num1小于等于num2")