some `minor` fix

ZhiHu_Python_Engineer_JD.py

class ZhihuDev(Developer):
    @property
    def characteristics(self):
        return set(["TeamWork", "Devoted", "Creative"])

    @property
    def skills(self):
        return {
            "Language"  : ["Python","Erlang", "Go", "C/C++"],
            "OS"        : ["Linux", "OS X", "BSD UNIX"],
            "Tool"      : ["Vim", "Emacs", "Git"],
            "Framework" : ["Tornado", "Gevent", "Flask"],
            "Network"   : ["TCP/IP", "ZeroMQ"]}
    
    @property
    def is_geek(self):
        return True