> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pysquirrels.com/llms.txt
> Use this file to discover all available pages before exploring further.

# DataSource

> Base type for data source objects used by parameters

Abstract base class for all data source classes. Data sources populate parameter options from lookup tables or queries.

In user code, `DataSource` appears as the common type for concrete data source classes that you construct to configure parameters; you should not instantiate `DataSource` itself directly. Use one of the concrete implementations:

* [SelectDataSource](/references/python/datasources/selectdatasource)
* [DateDataSource](/references/python/datasources/datedatasource)
* [DateRangeDataSource](/references/python/datasources/daterangedatasource)
* [NumberDataSource](/references/python/datasources/numberdatasource)
* [NumberRangeDataSource](/references/python/datasources/numberrangedatasource)
* [TextDataSource](/references/python/datasources/textdatasource)

When defining lookup-backed parameters, use the concrete classes from the `data_sources` module rather than `DataSource` itself.

If `DataSource` is needed for type annotation, it can be imported from the `squirrels.types` or `squirrels` module.