fn not_found() -> Result<Response<Body>> {
    let res = Response::builder()
        .status(StatusCode::NOT_FOUND)
        .body(NOT_FOUND.into())
        .unwrap();
    Ok(res)
}
/// returns a result contains not found error.
returns a result contains not found error.
returns a result contains not found error .
fn not_found() -> Result<Response<Body>> {
    let res = Response::builder()
        .status(StatusCode::NOT_FOUND)
        .body(NOT_FOUND.into())
        .unwrap();
    Ok(res)
}
fn not_found ( ) -> Result < Response < Body > > { let res = Response :: builder ( ) . status ( StatusCode :: NOT_FOUND ) . body ( NOT_FOUND . into ( ) ) . unwrap ( ) ; Ok ( res ) }
returns a result contains not found error.
returns a result contains not found error .