What are the key features of a sustainable city, and how do they contribute to a better quality of life for its residents? Your response should contain at least 3 bullet points. Use the markdown bullet points such as: * This is point 1. Also, highlight at least 2 sections in your answer with markdown, i.e., *highlighted section*. Finally, your response should contain at least 2 paragraphs. Paragraphs are separated with the markdown divider: ***
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