Polish translation tracking

This issue is for tracking and coordination of the Polish translation.

Contribution:

• add a comment indicating which page you'll be translating
• upon finishing, create PR and wait for reviews
• update your post over here with PR number
• fix issues(if any)
• your work will be merged after it's been approved

Convention:
It's been suggested in other translation tracking issues to follow Spanish translators' approach of translating technical terms and displaying original English words on hover(using abbr tag). That shouldn't apply to Python keywords or any terms for which Polish translation is rarely used. The goal is to make the documentation user-friendly and easy to understand for beginners.