* Add boilerplate snippet into `examples/`
It is a partial backport of #70224
(partially cherry picked from commit 4816bb4f43)
* Refactor Python API examples and docs
PR #70446: it's a follow-up for #70445.
It includes a merge of `examples/scripts/uptime.py` and a similar
code snippet from `docs/docsite/rst/dev_guide/developing_api.rst`.
This patch also changes the docs RST file to include contents of
the example file instead of holding a copy of a similar code.
(cherry picked from commit 20bb915092)
be28e98cf2