AGENTS Guide for This Repository

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This repo is a chaptered Python learning codebase, not a single app/service; each top-level numbered folder (01_native_datatypes ... 15_testing) is mostly independent examples.
README.md is the canonical map of chapter intent and file-level examples; use it first to locate the right script before editing.
Most scripts are designed for direct execution and demonstration output (prints, inline calls), not reusable package APIs.

Common pattern: many files expose small demo functions, then dispatch from if __name__ == '__main__' using sys.argv[1] and locals()/globals() (example: 01_native_datatypes/02-numeric-types.py, 11_async/07-net-server.py).
__doc__ is frequently used as in-file theory notes; preserve and extend this style when adding educational examples (example: 04_decorators/01-debug-print.py).
15_testing/testing.py provides core demo functions (rle, sort) consumed by nearby test/demo files.

Install deps from root:
- python3 -m pip install -r requirements.txt
Run a chapter script directly from root (or its directory), e.g.:
- python3 11_async/07-net-server.py square_server
Run unittest example (from 15_testing/ so local import from testing import ... resolves):
- python3 -m unittest 02-unittest.py
Run pytest property examples:
- python3 -m pytest 15_testing/04-property.py

TCP demo flow is coupled by host/port 127.0.0.1:10001:
- server: 11_async/07-net-server.py or 11_async/08-async-server.py or 11_async/09-async-server2.py
- client: 11_async/06-net-client.py
Module/package demo flow:
- 14_modules/02-packages.py imports small_package.package_file and demonstrates lazy import via importlib.
File-IO iterator demo expects relative files in 10_iterators/ (file1.txt, file2.txt) in 10_iterators/07-io.py.

Prefer small, single-topic educational scripts over large abstractions.
Keep examples executable with minimal setup; avoid introducing framework scaffolding.
When adding examples, follow existing naming style (NN-topic.py) inside the relevant chapter folder.
Avoid breaking relative-import assumptions in chapter demos (many imports are intentionally local-directory based).
Preserve demonstrative print-based output unless the file already uses tests/assertions.

Confirm target chapter/file intent in README.md.
Verify whether the file is a standalone demo, a test module, or a helper module (15_testing/testing.py).
If editing 11_async or 10_iterators, check related peer files that provide input/client behavior.
Run the narrowest relevant command (single script or single test file), not full-repo test sweeps.