# RetentionExemption

## class nominal.core.RetentionExemption(dataset_rid, source_id, start, end, description)

Bases: [`object`](https://docs.python.org/3/builtins/functions.html#object "(in Python v3.15)")

A time range of a dataset’s data that retention must not delete.

### dataset_rid: str

RID of the dataset the exemption applies to.

### source_id: str

Identifies what owns the exemption. Locking a run creates exemptions whose source ID is the run’s RID.

### start: int

Start of the exempt range, in UTC nanoseconds.

### end: int

End of the exempt range, in UTC nanoseconds.

### description: str | None

Why the range is exempt, if one was given.