Mypy errors since v4.51.0

[jc-louis]

@cyyever this is a direct result of #37022 which marked the library as typed.

from typing import reveal_type

from transformers import Trainer, PreTrainedModel

def mypy_errors(trainer: Trainer, model: PreTrainedModel) -> None:
    reveal_type(trainer)
    reveal_type(trainer.train())
    trainer.train()
    model.dequantize()

Using mypy test.py, I get the following errors:

script.py:5: note: Revealed type is "def (*args: Any, **kwargs: Any) -> transformers.utils.dummy_pt_objects.Trainer"
script.py:8: note: Revealed type is "transformers.utils.dummy_pt_objects.Trainer"
script.py:9: error: "Trainer" has no attribute "train"  [attr-defined]
script.py:9: note: Revealed type is "Any"
script.py:10: error: "Trainer" has no attribute "train"  [attr-defined]
script.py:11: error: "PreTrainedModel" has no attribute "dequantize"  [attr-defined]

Theses errors are false positives, it seems like there is a config issue, all types are pulled from dummy_pt_objects.py

---

• transformers version: 4.51.0
• Platform: macOS-14.7.3-arm64-arm-64bit
• Python version: 3.12.3

[cyyever]

Try

from transformers.trainer import Trainer    
from transformers.modeling_utils  import PreTrainedModel

[jc-louis]

@cyyever this does indeed fix the issue, thanks!

However, doing from transformers import Trainer is the recommended way in the docs, is there any fix planed?

[cyyever]

We should add __all__ to all exported symbols.

[cyyever]

@jc-louis I submitted a PR for this issue. Can you install it and check?

[jc-louis]

@cyyever I confirm it does fix the issue 👍

[jonoillar]

Does someone know if mypy lets you ignore errors related to a specific python object ?

Like when I get those errors:

error: "PreTrainedModel" has no attribute "generate"  [attr-defined]
error: "PreTrainedModel" has no attribute "eval"  [attr-defined]
error: "PreTrainedModel" not callable  [operator]

I would simply like to ignore the errors "attr-defined", "operator" related to "PreTrainedModel"