Send the response header and log the response code.

def send_response(self, code, message=None):
        """Send the response header and log the response code."""
        self.log_request(code)
        if message is None:
            message = code in self.responses and self.responses[code][0] or ""
        if self.request_version != "HTTP/0.9":
            hdr = "%s %d %s\r\n" % (self.protocol_version, code, message)
            self.wfile.write(hdr.encode("ascii"))