{"blocks": [{"key": "1c60941b", "text": "Question", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "029d3939", "text": "Design a recommendation system for users and items: discuss model choice (e.g., NMF), data fetching with multiple servers and a reverse proxy, and data storage (user, item, and interaction tables).", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}], "entityMap": {}}