比较傻瓜的小程序……

__author__ = 'Arthur'

def _private_1(name):
    return 'Hello, %s' %name

def _private_2(name):
    return 'Hi, %s' %name

def greeting(name):
    if len(name) <= 5:
        return _private_1(name)
    else:
        return _private_2(name)

name1 = input('please input your name:')

print (greeting(name1))