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: utils.rs
    path of file: ./repos/sysinfo/src/windows
    
    the code of the file until where you have to start completion: // Take a look at the license at the top of the repository in the LICENSE file.

use windows::core::{PCWSTR, PWSTR};
use windows::Win32::Foundation::{self, FILETIME};
use windows::Win32::System::Registry::{
    RegCloseKey, RegOpenKeyExW, RegQueryValueExW, HKEY, KEY_READ, RE
    
pub(crate) fn get_reg_value_u32(hkey: HKEY, path: &str, field_name: &str) -> Option<[u8; 4]> {
    let c_path = utf16_str(path);
    let c_field_name = utf16_str(field_name);

    unsafe {
        let new_key = RegKey::open(hkey, &c_path)?;
        let mut buf_len: u32 = 4;
        let mut buf = [0u8; 4];

        new_key
            .get_value(&c_field_name, &mut buf, &mut buf_len)
            .map(|_| buf)
            .ok()
    }
}