28 pub type Attributes = HashMap<usize, usize>;  typedef
82     async fn write(&self, pkt: &rtp::packet::Packet, attributes: &Attributes) -> Result<usize>;  in write()
88             &Attributes,
98     async fn write(&self, pkt: &rtp::packet::Packet, attributes: &Attributes) -> Result<usize> {  in write()
107     async fn read(&self, buf: &mut [u8], attributes: &Attributes) -> Result<(usize, Attributes)>;  in read()  argument
113             &Attributes,
114         ) -> Pin<Box<dyn Future<Output = Result<(usize, Attributes)>> + Send + Sync>>)
123     async fn read(&self, buf: &mut [u8], attributes: &Attributes) -> Result<(usize, Attributes)> {  in read()  argument
135         attributes: &Attributes,  in write()  argument
142             &Attributes,
156         attributes: &Attributes,  in write()  argument
166     async fn read(&self, buf: &mut [u8], attributes: &Attributes) -> Result<(usize, Attributes)>;  in read()  argument
172             &Attributes,
173         ) -> Pin<Box<dyn Future<Output = Result<(usize, Attributes)>> + Send + Sync>>)
183     async fn read(&self, buf: &mut [u8], attributes: &Attributes) -> Result<(usize, Attributes)> {  in read()  argument