write method
Implementation
void write(String msg) {
final now = DateTime.now();
final time =
"${now.hour.toString().padLeft(2, '0')}:${now.minute.toString().padLeft(2, '0')}:${now.second.toString().padLeft(2, '0')}";
final logMsg = '[$time]: $msg';
_file?.writeAsStringSync(logMsg, mode: FileMode.append);
}