Integrating Python into your day-to-day ArcGIS work is highly recommended when dealing with large amounts of geospatial data. Python for ArcGIS Pro aims to help you get your work done faster, with ...

This is an updated "How To" originally posted in October 2013 on 'jonah's maps'. You can find this post there as well. All of these options work off of AGOL's ability to add a tile layer from the web.