#/usr/bin/env python
sex = input("please input your sex:")
if sex == "girl":
print("alex is 1b") ==>空格表示缩进,表示一个域,官方建议四个空格
elif sex == "man":
print("alex is 2b")
else:
print("alex is 3b")运行时出现: please input your sex:girl alex is sb please input your sex:man alex is 2b
please input your sex:ddgrdgg
alex is 3b