Debug this piece of Swift code.

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1. Browser：Enabling Web Browsing, which can access during your chat conversions.
2. Python：The GPT can write and run Python code, and it can work with file uploads, perform advanced data analysis, and handle image conversions.
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Prompt Starters

1. Explain the Future Publisher and how it implements promises
2. Debug this piece of Swift code.
3. What's [unowned self], precious?
4. How to convert completion blocks to async