# Source panel

The options on this tab vary depending on the script source.

* **Embed** (default): Select this option to embed the Python script specified in the **Manual Python script** field. The transformation will run using this Python script.
* **Link from file**: If you choose this option, you can link out to virtual file systems.

Enter the following information in the fields for the specified source.

| Option                                                 | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| ------------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Manual Python script** (**Embed**)                   | Enter the Python script (`#` python script) you want to embed for this transformation.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| **Location** (**Link from file**)                      | Indicates the file system or specific cluster where the python execution file you want to link from is located. For the supported file system types, see [VFS browser](https://docs.pentaho.com/pdia-data-integration/10.2-data-integration/data-integration-perspective-in-the-pdi-client/virtual-file-system-browser/vfs-browser-connecting-to-virtual-file-systems).                                                                                                                                                                                                                                                                                                                  |
| **File name** (**Link from file**)                     | <p>Specify the fully qualified URL of the local Python execution file you want to link from for this transformation.</p><p>Click <strong>Browse</strong> to navigate to the source file or folder in the <a href="../../../../data-integration-perspective-in-the-pdi-client/virtual-file-system-browser/vfs-browser-connecting-to-virtual-file-systems">VFS browser</a>. This field supports variable injections using <code>${}</code> notation.</p>                                                                                                                                                                                                                                   |
| **Use a Python virtual environment** (check box/field) | <p>Use this option if you have multiple versions of Python installed locally and you want to select a particular version for this step. Options include:- Select this check box if you want to specify a version of Python to run other than the default version. In the field, enter the version of Python you want to use to run this transformation. Click the <strong>Browse</strong> button to locate the Python execute file on your local server. This field supports variable injections using <code>${}</code> notation.</p><ul><li>Clear this check box if you have previously installed Python on your system and want to use this version as your default version.</li></ul> |