# Saver **`class Saver(config)`** Bases: [`BatchedStep`](../technical/libnlp/steps/standard.md#squirro.lib.nlp.steps.batched_step.BatchedStep) The [`Saver`](#squirro.lib.nlp.steps.savers.Saver) step saves specified fields to some external store for each [`Document`](../technical/libnlp/base.md#squirro.lib.nlp.document.Document). Parameters - `step` ([`str`](https://docs.python.org/3.11/library/stdtypes.html#str)) – saver - `type` ([`str`](https://docs.python.org/3.11/library/stdtypes.html#str)) – Type of [`Saver`](#squirro.lib.nlp.steps.savers.Saver) - `fields` ([`list`](https://docs.python.org/3.11/library/stdtypes.html#list)`, ``None`) – list of fields to write back