async def METHOD_NAME(request, handler):
    global g_response_server, g_response_add_date
    response = await handler(request)
    if g_response_server:
        response.headers[b'Server'] = g_response_server
    if g_response_add_date:
        response.headers[b'Date'] = formatdate(timeval=None, localtime=False, usegmt=True)            
    return response