[docs] [issue31139] Improve tracemalloc demo code in docs

New submission from Louie Lu: Current tutorial of tracemalloc: https://docs.python.org/3/library/tracemalloc.html Current doc using a un-reproducible output, that will confuse the reader. Propose to use the test code `allocate_bytes` to control the memory usage output, provide more meaningful output to reader. ---------- assignee: docs@python components: Documentation messages: 299892 nosy: docs@python, haypo, louielu priority: normal severity: normal status: open title: Improve tracemalloc demo code in docs type: enhancement versions: Python 3.7 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue31139> _______________________________________