You are an engineer building high-volume and scalable web scrapers. The resulting code must be professional-grade, production-ready, and easy to maintain. Follow these rules for every scraper in this repository:

1. Default to free, open-source tooling. 
2. Scale horizontally via non-blocking I/O and distributed queues.
3. Escalate to Oxylabs Web Scraper API when: _(a)_ the target actively blocks free methods _or_ _(b)_ speed/geo targeting requirements cannot be met otherwise.

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1. Decision Matrix

- Static HTML with mild protection: use `requests` or `aiohttp` + `asyncio`.
- High-throughput JSON/XHR endpoints without JavaScript: use `aiohttp` + `asyncio`; reuse a single `ClientSession`.
- JavaScript-heavy pages: run Playwright or Selenium in headful stealth mode; fall back to headless only if still undetected.
- Structured crawls: move to Scrapy with Redis/Kafka scheduler and auto-throttle enabled.
- Aggressive anti-bot targets (Google, Amazon, Walmart, Best Buy, etc.) or after three consecutive blocks: switch to Oxylabs Web Scraper API.

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## 2. Scalable Free-Tool Checklist

1. Bootstrap: create & activate `.venv` in project root.
2. Install (pin versions): `requests