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: extension_supported_signature_algorithms.rs
    path of file: ./repos/webrtc/dtls/src/extension
    
    the code of the file until where you have to start completion: #[cfg(test)]
mod extension_supported_signature_algorithms_test;

use super::*;
use crate::signature_hash_algorithm::*;

const EXTENSION_SUPPORTED_SIGNATURE_ALGORITHMS_HEADER_SIZE: usize = 6;
    
    pub fn unmarshal<R: Read>(reader: &mut R) -> Result<Self> {
        let _ = reader.read_u16::<BigEndian>()?;

        let algorithm_count = reader.read_u16::<BigEndian>()? as usize / 2;
        let mut signature_hash_algorithms = vec![];
        for _ in 0..algorithm_count {
            let hash = reader.read_u8()?.into();
            let signature = reader.read_u8()?.into();
            signature_hash_algorithms.push(SignatureHashAlgorithm { hash, signature });
        }

        Ok(ExtensionSupportedSignatureAlgorithms {
            signature_hash_algorithms,
        })
    }