# Import files

> Learn how to import files into the Pixyz Asset Transformer SDK for processing and conversion.

API functions:

* [io.importScene](/asset-transformer-sdk/2026.4/api/python/io_functions.md#importscene): import one file at a time. Function is multi-threaded when possible (depending on format).
* [io.importFiles](/asset-transformer-sdk/2026.4/api/python/io_functions.md#importfiles): import multiple files at a time. If possible, each file will be imported in a different thread, making it more efficient than just looping over files and using `io.importScene`.

> **Note:**
>
> Check IO [preferences](./../preferences) to modify import settings such as PMI loading, coordinate system options, alternative importers...

## Load Pixyz files (.pxz)

`.pxz` is Pixyz Engine proprietary file format. Saving/Loading .pxz files is extremely fast and we recommend using it if going from one instance of Pixyz to another one.

API functions:

* [core.load](/asset-transformer-sdk/2026.4/api/python/core_functions.md#load): load and replace the current scene by the one from the .pxz file
* [core.save](/asset-transformer-sdk/2026.4/api/python/core_functions.md#save): save the current scene as .pxz

## Related Topics

* [Supported file formats](./supported-formats)
* [Importing Alias files](./import-alias)
* [Importing VRED files](./import-vred)
* [Importing RVM files](./import-rvm)
* [Importing ReCap files](./import-recap)