'Send the response header only.'

def send_response_only(self, code, message=None):

    if (message is None):
        if (code in self.responses):
            message = self.responses[code][0]
        else:
            message = ''
    if (self.request_version != 'HTTP/0.9'):
        if (not hasattr(self, '_headers_buffer')):
            self._headers_buffer = []
        self._headers_buffer.append(('%s    %d    %s\r\n' % (self.protocol_version, code, message)).encode('latin-1', 'strict'))
