# ExtractorError

## exception nominal.exceptions.ExtractorError

Bases: [`NominalError`](https://dev.nominal.io/python/ref/generated/nominal.exceptions.NominalError.md#nominal.exceptions.NominalError "nominal.exceptions.NominalError")

Raised when the extractor contract is violated (missing input, wrong output count, …).

Exported as `nominal.experimental.extractor.ExtractorError`, which is where authors meet it.