Are Codelabs free?

How to Use CodeLab

Python on Google Cloud integrates with Cloud Monitoring, Cloud Trace, Cloud Logging, and Error Reporting , allowing you to transparently instrument live production applications to rapidly diagnose performance bottlenecks and software bugs.

Codelabs is free while Qwiklabs is not. There is no constant price for qwiklabs lab sessions. It varies one from the another. The pricing is done on the basis of credit where 1 credit is equivalent to 1 US dollar.