You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: rtp_header.rs
    path of file: ./repos/xiu/protocol/rtsp/src/rtp
    
    the code of the file until where you have to start completion: use byteorder::BigEndian;
use bytes::BytesMut;
use bytesio::bytes_errors::BytesReadError;
use bytesio::bytes_errors::BytesWriteError;
use bytesio::bytes_reade
    
    fn marshal(&self) -> Result<BytesMut, BytesWriteError> {
        let mut writer = BytesWriter::default();

        let byte_1st: u8 = (self.version << 6)
            | (self.padding_flag << 5)
            | (self.extension_flag << 4)
            | (self.cc & 0x0F);
        writer.write_u8(byte_1st)?;

        let byte_2nd: u8 = (self.marker << 7) | self.payload_type;
        writer.write_u8(byte_2nd)?;

        writer.write_u16::<BigEndian>(self.seq_number)?;
        writer.write_u32::<BigEndian>(self.timestamp)?;
        writer.write_u32::<BigEndian>(self.ssrc)?;

        for csrc in &self.csrcs {
            writer.write_u32::<BigEndian>(*csrc)?;
        }

        Ok(writer.extract_current_bytes())
    }