check users are actually recieved in upload to s3 (#102760)
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### <samp>๐ค Generated by Copilot at 5927156</samp>
### Summary
๐๐งน๐
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1. ๐ - This emoji represents the retry logic that is added to the script, which loops until the command succeeds or reaches the maximum number of attempts.
2. ๐งน - This emoji represents the cleanup and simplification of the code, which removes clutter and makes it easier to understand and maintain.
3. ๐ - This emoji represents the data analysis and visualization that is enabled by uploading the external contribution stats to Rockset, which allows for exploring and sharing insights on the open source community.
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This pull request improves the `upload_external_contrib_stats.py` script and the `nightly-rockset-uploads.yml` workflow. It makes the script more efficient and robust, and increases the retry logic for the Rockset upload command.
> _Oh we are the coders of the open source sea_
> _And we upload stats to Rockset with glee_
> _But sometimes the network is slow or breaks down_
> _So we retry the command and we don't let it drown_
### Walkthrough
* Increase the number of retries for uploading external contribution stats to Rockset to avoid failures ([link](https://github.com/pytorch/pytorch/pull/102760/files?diff=unified&w=0#diff-a0d80a44a0694ddbddd6d8cf9484f5b850268a34117c8caf1fc071ad59895f9fL35-R35))
* Simplify the logic of uploading external contribution stats to Rockset by removing the loop and adding assertions and print statements ([link](https://github.com/pytorch/pytorch/pull/102760/files?diff=unified&w=0#diff-ac022823c08d71df6cc85aae7f2ca50a1ec71e5f9eb9371ac563c12cf52b750cL137-R146))
* Remove unused import of `read_from_s3` from `upload_external_contrib_stats.py` to clean up the code ([link](https://github.com/pytorch/pytorch/pull/102760/files?diff=unified&w=0#diff-ac022823c08d71df6cc85aae7f2ca50a1ec71e5f9eb9371ac563c12cf52b750cL11-R11))
Pull Request resolved: https://github.com/pytorch/pytorch/pull/102760
Approved by: https://github.com/kit1980
