import http.server
import urllib.parse

class newHandler(http.server.BaseHTTPRequestHandler):

    def do_GET(self):
        self.send_response(200)
        self.end_headers()

        parseUrl = urllib.parse.urlparse(self.path)
        path = parseUrl.path

        if path == "/Yang":
            msg1 = "<a href='/Ying'>" + path + "</a>"
        elif path == "/Ying":
            msg1 = "<a href='/Yang'>" + path + "</a>"

        self.wfile.write(msg1.encode('utf-8'))



PORT =  4096
HANDLER = newHandler
ADDRESS = ('', PORT)

SERVER = http.server.HTTPServer(ADDRESS, HANDLER)
SERVER.serve_forever()