* 📝 Update docs, require Python 3.8+, drop 3.7
* 🔧 Update pyproject.toml, drop support for Python 3.7, require Python 3.8+
* 👷 Update CI GitHub Actions, drop support for Python 3.7, require 3.8+
* 📝 Update docs' references to Python 3.6 and 3.7, use Python 3.8
* 📝 Add docs recommending Union over Optional
* 📝 Update docs recommending Union over Optional
* 📝 Update source examples for docs, recommend Union over Optional
* 📝 Update highlighted lines with updated source examples
* 📝 Update highlighted lines in Markdown with recent code changes
* 📝 Update docs, use Union instead of Optional
* ♻️ Update source examples to recommend Union over Optional
* 🎨 Update highlighted code in Markdown after moving from Optional to Union
