use fallback;
use crateResponse;
use crateALLOW;
use AllowedMethods;
/// The default fallback handler for incoming requests that don't match
/// any of the routes you registered.
///
/// It returns a `404 Not Found` response if the path doesn't match any of the
/// registered route paths.
/// It returns a `405 Method Not Allowed` response if the path matches a
/// registered route path but the method doesn't match any of its associated
/// handlers.
///
/// It also returns a `404 Not Found` response if the path allows all HTTP methods,
/// including custom ones.
pub async