#!/usr/bin/env python3
# -*- coding : utf-8 -*-

# normally , defined vars as ABC,PI,HIE is public.
# also , such as __name__ , those vars which begin and end with __ is special.
# those vars start with _ or __ but with a normal ending is private var.
# private func and var **should not** be quoted with others.(but can be)

# if a func don't need to be quoted outside,you should define it as a private func.
# and just use it to hide inside func details and thinking.

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


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


def greeting(name):
    if len(name) > 3:
        return _private_1(name)
    else:
        return _private_2(name)
