variables inside BaseHTTPRequestHandler Python

Question

I am creating a chatbot using Python and MS Bot Builder SDK for Python. The bot is a HTTPServer using a handler. What I want are variables to help me keeping track of the conversation, for example a message counter. But I can't get it to work, each time the bot receives a request (me sending something), it's like another handler is created, cause the number of messages is always 1. I'm not sure what is being called on each request.

Here is the (important) code:

class BotRequestHandler(BaseHTTPRequestHandler):
    count = 0

    @staticmethod
    def __create_reply_activity(request_activity, text):
        # not important

    def __handle_conversation_update_activity(self, activity):
        # not important

    def __handle_message_activity(self, activity):
        self.count += 1 ############## INCREMENTATION ##############
        self.send_response(200)
        self.end_headers()
        credentials = MicrosoftAppCredentials(APP_ID, APP_PASSWORD)
        connector = ConnectorClient(credentials, base_url=activity.service_url)
        reply = BotRequestHandler.__create_reply_activity(activity, '(%d) You said: %s' % (self.count, activity.text))
        connector.conversations.send_to_conversation(reply.conversation.id, reply)

    def __handle_authentication(self, activity):
        # not important

    def __unhandled_activity(self):
        # not important

    def do_POST(self):
        body = self.rfile.read(int(self.headers['Content-Length']))
        data = json.loads(str(body, 'utf-8'))
        activity = Activity.deserialize(data)

        if not self.__handle_authentication(activity):
            return

        if activity.type == ActivityTypes.conversation_update.value:
            self.__handle_conversation_update_activity(activity)
        elif activity.type == ActivityTypes.message.value:
            self.__handle_message_activity(activity)
        else:
            self.__unhandled_activity()


class BotServer(HTTPServer):
    def __init__(self):
        super().__init__(('localhost', 9000), BotRequestHandler)

    def _run(self):
        try:
            print('Started http server')
            self.serve_forever()
        except KeyboardInterrupt:
            print('^C received, shutting down server')
            self.socket.close()

server = BotServer()
server._run()

What I get if enter the message 'a' 4 times is '(1) You said: a' 4 times. I tried overrifing init method of BaseHTTPRequestHandler but it didn't work.

For those who know: the thing is with Python SDK we don't have Waterfall dialogs like in Node.js, or I didn't find how it works, if someone knows just tell me, cause here I need to keep track of a lot of things from the user and I need variables. And I really want to use Python because I need some ML and other modules in Python.

Thank you for your help.