Multithreaded SimpleHTTPServer with basic auth

server.py

import os
import base64
import SocketServer
import BaseHTTPServer
import SimpleHTTPServer

class AuthHandler(SimpleHTTPServer.SimpleHTTPRequestHandler):
    ''' Main class to present webpages and authentication. '''
    def do_AUTHHEAD(self):
        self.send_response(401)
        self.send_header('WWW-Authenticate', 'Basic realm=\"Auth\"')
        self.send_header('Content-type', 'text/html')
        self.end_headers()

    def do_GET(self):
        global keys
        ''' Present frontpage with user authentication. '''
        if self.headers.getheader('Authorization') == None:
            self.do_AUTHHEAD()
            self.wfile.write('No auth header received')
        else:
            for key in keys:
                if self.headers.getheader('Authorization') == 'Basic ' + key:
                    SimpleHTTPServer.SimpleHTTPRequestHandler.do_GET(self)
                    return
            else:
                self.do_AUTHHEAD()
                self.wfile.write(self.headers.getheader('Authorization'))
                self.wfile.write('Not authenticated')

class ThreadingSimpleServer(SocketServer.ThreadingMixIn,
                            BaseHTTPServer.HTTPServer):
    pass

import sys

if sys.argv[1:]:
    port = int(sys.argv[1])
else:
    port = 8000
keys = map(base64.b64encode, ['USERNAME:PASSWORD'])

os.chdir('files')

server = ThreadingSimpleServer(('', port), AuthHandler)
try:
    server.serve_forever()
except KeyboardInterrupt:
    print('Finished')