Fri, 08 Sep 2017 11:53:48 +0300fix problem if _should_write is called by expired timer after
Andrey Skvortsov <andrej.skvortzov@gmail.com> [Fri, 08 Sep 2017 11:53:48 +0300] rev 1795
fix problem if _should_write is called by expired timer after
termination of wx application.