› Advanced » The image viewer has a plugin system which uses the Python scripting language. If you activate the Python console, you can gain direct access to a Python interpreter from inside the image viewer, which you can then use to write scripts or programmatically manipulate images, for example.
Before you can activate the Python console, you will need to install eog-plugins.
Once eog-plugins is installed, click Edit ▸ Preferences and go to the Plugins tab.
Check Python Console and click Close.
Click Tools ▸ Python Console to bring up the console.