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: json.rs
    path of file: ./repos/gosub-engine/crates/gosub_config/src/storage
    
    the code of the file until where you have to start completion: use crate::settings::Setting;
use crate::StorageAdapter;
use gosub_shared::types::Result;
use log::warn;
use serde_json::Value;
use std::collections::HashMap;
use std::fs;
use std::fs::File;
use std::io::{Read, Seek, Write};
use std::sync::Mutex;

pub struct JsonStorageAdapter {
    path: String,
    elements: Mutex<HashMap<String, Setting>>,
}

impl TryFrom<&String> for JsonStorageAdapter {
    type Error = anyhow::Er
    
    fn write_file(&mut self) {
        // @TODO: We need some kind of OS lock file here. We should protect against concurrent threads but also
        // against concurrent processes.
        let mut file = File::open(&self.path).expect("failed to open json file");

        let json = serde_json::to_string_pretty(&self.elements).expect("failed to serialize");

        file.set_len(0).expect("failed to truncate file");
        file.seek(std::io::SeekFrom::Start(0))
            .expect("failed to seek");
        file.write_all(json.as_bytes())
            .expect("failed to write file");
    }