title: How safe is it to import a module multiple times?
body: <p>I've been wondering this for a while: Is it guaranteed to be safe to import a module multiple times? Of course, if the module performs operating systems things like write to files or something, then probably not, but for the majority of simple modules, is it safe to simply perform imports willy-nilly? Is there a convention that governs the global state of a module?</p>