I am using an API key in some Python code which I am looking to distribute. This API key is for Google Maps. Are there any security issues with regards to distributing this API key and if so, how is it best to hide this?
You could obfuscate the key in various ways, but it's not worth the effort.  Obfuscation is a weak way to protect information, and in this case your information's security isn't especially critical anyway.
The point of the API key is largely so that the API vendor (Google, here) can monitor, throttle, and revoke your application's use of their service.  It is meant to be private, and you shouldn't share it carelessly or intentionally, but it isn't the end of the world if somebody else gets their hands on it.
Hiding API key in code (Python)