Check client IP. Accept requests only from telegram servers.

        :return:

def check_ip(self):
        """
        Check client IP. Accept requests only from telegram servers.

        :return:
        """
        # For reverse proxy (nginx)
        forwarded_for = self.request.headers.get('X-Forwarded-For', None)
        if forwarded_for:
            return forwarded_for, _check_ip(forwarded_for)

        # For default method
        peer_name = self.request.transport.get_extra_info('peername')
        if peer_name is not None:
            host, _ = peer_name
            return host, _check_ip(host)

        # Not allowed and can't get client IP
        return None, False