Add num_warmup_steps/n_training_steps > 0 validation to scheduler fun…
Author: kaivalya-cyber
Pull request: yes
Labels: name: Code agent slop

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# What does this PR do?

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Fixes # (issue)

## Code Agent Policy

The Transformers repo is currently being overwhelmed by a large number of PRs and issue comments written by
code agents. We are currently bottlenecked by our ability to review and respond to them. As a result, 
**we ask that new users do not submit pure code agent PRs** at this time. 
You may use code agents in drafting or to help you diagnose issues. We'd also ask autonomous "OpenClaw"-like agents
not to open any PRs or issues for the moment.

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This is a rapidly-evolving situation that's causing significant shockwaves in the open-source community. As a result, 
this policy is likely to be updated regularly in the near future. For more information, please read [`CONTRIBUTING.md`](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md).

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## Before submitting
- [x] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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## Who can review?

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Models:

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Comments:
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### CI recap

**Dashboard:** [View test results in Grafana](https://transformers-ci.lor-e.huggingface.cool/d/pytest-observability-by-pr/pytest-observability-branch?var-pr=47193)
**Latest run:** [28996542160:2](https://github.com/huggingface/transformers/actions/runs/28996542160)
**Result:** `failure` | **Jobs:** 15 | **Tests:** 170,727 | **Failures:** 1 | **Duration:** 18h 31m

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