[docs] [issue43834] Use context manager in StringIO example

Raymond Hettinger <raymond.hettinger@gmail.com> added the comment: Let's leave the example as-is. The principal use case for these objects is to pass them into other APIs that require file-like objects. Those can't always be put in a context manager. For this example, we mainly want to communicate that getvalue() must be called before the object is closed. The current form communicates that clearly. Thanks for the suggestion. ---------- nosy: +rhettinger resolution: -> rejected stage: patch review -> resolved status: open -> closed _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue43834> _______________________________________