Function external_storage_export::export::read_external_storage_into_file

pub async fn read_external_storage_into_file(
    input: &'_ mut (dyn AsyncRead + '_ + Unpin), 
    output: &'_ mut (dyn Write + '_), 
    speed_limiter: &'_ Limiter<CoarseClock>, 
    expected_length: u64, 
    min_read_speed: usize
) -> Result<(), Error>