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It surprises me that the http-after does not seem to respect Retry-After headers if I am reading the codebase properly. It's pretty easy to add directly into the requests library using an adapter and the Requests Retry object like so: https://github.com/fsspec/filesystem_spec/blob/262f664574e091228251b467ac92b2a6c327034b/fsspec/implementations/dbfs.py#L54 or by parsing the proper HTTP field. This would reduce the amount of errors encountered I find when trying to stream data lots of data from the Hub and would also implement nice effective client-side rate limiting.

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Respect Retry-After headers, especially on 429 status codes.

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