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: multithreading.rs
    path of file: ./repos/divans/src
    
    the code of the file until where you have to start completion: #![cfg(feature="std")]
use core;

use std::sync::{Arc, Mutex, Condvar};
use threading::{SerialWorker, MainToThread, ThreadToMain, CommandResult, ThreadData, NUM_SERIAL_COMMANDS_BUFFERED, NUM_DATA_BUFFERED,};
use slice_util::{AllocatedMemoryRange, AllocatedMemoryPrefix};
use alloc::{Allocator, SliceWrapper, SliceWrapperMut};
use alloc_util::RepurposingAlloc;
use cmd_to_raw::DivansReco
    
    fn drop(&mut self) {
        let epoch_d = self.start.duration_since(std::time::UNIX_EPOCH).unwrap_or(Duration::new(0,0));
        let epoch = (epoch_d.as_secs()%100) * 100 + u64::from(epoch_d.subsec_nanos()) / 10000000;
        let start_log = self.start.elapsed().unwrap_or(Duration::new(0,0));
        use std;
        use std::io::Write;
        let stderr = std::io::stderr();
        let mut handle = stderr.lock();
        writeln!(handle, "{:04}:{:02}:{:09}:LOG_START", epoch, start_log.as_secs(), start_log.subsec_nanos()).unwrap();
        for entry in self.log[..self.log_offset as usize].iter() {
            writeln!(handle, "{:04}:{:02}:{:09}:{:?}:{}", epoch, entry.2.as_secs(), entry.2.subsec_nanos(), entry.0, entry.1).unwrap();
        }
        let fin_log = self.start.elapsed().unwrap_or(Duration::new(0,0));
        writeln!(handle, "{:04}:{:02}:{:09}:LOG_FLUSH:{:?}ns", epoch, fin_log.as_secs(), fin_log.subsec_nanos(), fin_log - start_log).unwrap();
    }