Function encode_blocked_range 

fn encode_blocked_range<W: Write + ?Sized, F>(
    out: &mut W,
    start: usize,
    end: usize,
    write_item: F,
) -> Result<(), ArrowError>
where
    F: FnMut(&mut W, usize) -> Result<(), ArrowError>,

Encode a blocked range of items with Avro array block framing.

write_item must take (out, index) to maintain the “out-first” convention.