Whether instantiation is premature?
https://github.com/huggingface/transformers/blob/515ed3ad2a11a6b0cd9800b2ad4d3b313fdaea8c/src/transformers/feature_extraction_utils.py#L429

For example my code is:
```python3 
processor = LayoutXLMProcessor.from_pretrained('microsoft/layoutxlm-base', apply_ocr=False)
```
I don't need to use OCR, but pytesseract still has to be installed. 
Would it be a good solution to this kind of problem if the parameters were updated with kwargs before instantiation？
@NielsRogge any suggestions?<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/master/CONTRIBUTING.md) are likely to be ignored.<|||||>Hi,

Thanks for the issue and apologies for the late reply. I'll look into this.<|||||>cc'ing @sgugger. 

The problem is here is that, 'microsoft/layoutxlm-base' on the hub has a `preprocessor_config.json` which has `apply_ocr = True`, hence the `from_pretrained()` method will raise the error that PyTesseract should be installed. However, the additional kwarg `apply_ocr=False` is only taken into account after this.<|||||>Yes, that is the `FeatureExtractionMixin` is coded. I suggest moving the `requires_backends(self, "pytesseract")` to the call method instead of the init to solve this issue.