The Nutshell Python SDK by Emil Stenström allows API interaction and provides JSON-RPC protocol. Resources explain how to create an API key and a username to make calls. Documentation available at https://www.nutshell.com/api/detail/class_core.html
A few months after releasing the Google My Business API v3.0, Google has released v3.1. The release includes many new features including push notifications for new listings and reviews, easier navigation to Google Maps, and more. Additionally, Google mentioned a number of new features soon to come.