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pub fn decode_some_bytes(bytes: &[u8]) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
    // first two bytes should be id (u16)
    // little endian
    let index: u16 = (bytes[0] as u16) << 8 | bytes[1] as u16;
    println!("index: {}", index);

    // second two bytes should be flags
    // going to skip the second byte for now
    let is_question = bytes[2] & 0b1000_0000 == 0;
    let op_code = bytes[2] & 0b0111_1000 >> 3;
    let is_truncated = bytes[2] & 0b0000_0010 != 0;
    let is_recursive = bytes[2] & 0b0000_0001 != 0;

    // starting from 4th index
    let num_of_questions: u16 = (bytes[4] as u16) << 8 | bytes[5] as u16;
    let num_of_arr: u16 = (bytes[6] as u16) << 8 | bytes[7] as u16;
    let num_of_ar: u16 = (bytes[8] as u16) << 8 | bytes[9] as u16;
    let num_of_additional_rrs: u16 = (bytes[10] as u16) << 8 | bytes[11] as u16;

    // answer section starting from 12th index
    let mut cur_idx = 12;
    let mut q_name_array: Vec<&str> = Vec::new();
    while bytes[cur_idx] != 0x00 {
        let len = bytes[cur_idx];
        let segment = from_utf8(&bytes[cur_idx + 1..cur_idx + 1 + len as usize])?;
        q_name_array.push(segment);
        cur_idx += len as usize + 1;
    }

    // query type

    println!("is_question: {}", is_question);
    println!("op_code: {}", op_code);
    println!("is_truncated: {}", is_truncated);
    println!("is_recursive: {}", is_recursive);
    println!("num_of_questions: {}", num_of_questions);
    println!("num_of_arr: {}", num_of_arr);
    println!("num_of_ar: {}", num_of_ar);
    println!("num_of_additional_rrs: {}", num_of_additional_rrs);
    println!("q_name_array: {:?}", q_name_array);

    Ok(())
}