You can use ArcGIS Python API to automate common tasks, such as creating and managing groups, publishing and updating items, and performing powerful visualization and data analysis.
In addition to batch processing scripts, the API can be used in a browser-based interactive scripting environment called Jupyter Notebook. The notebook environment provides an interface to execute code, visualize portal items, users, and groups, as well as view web layers, maps, and scenes interactively.
The API is built as modules that make it straightforward to learn and use. The gis module is the entry point and provides an information model to access and program your portal. The features and raster modules allow access to feature and raster layers, as well as the ability to perform analysis on these layers. The geoanalytics module allows execution of GeoAnalytics Tools. To learn more about the rest of the modules and the architecture of the API, see the API overview.
The API is distributed as a Python package and can be installed using conda, which is a popular Python package and environment management system. The instructions for setup are documented on the ArcGIS for Developers site.