How to get the x,y,z value of one cluster(with the biggest number of points) after clustering?

**Is your feature request related to a problem? Please describe.**
Hi, I see the python example clustering.py, I run the code and I see the points are painted by different colors, while, I wondering how to choose one of the cluster by some features? And get the x,y,z value of the cluster I choose.

**Describe the solution you'd like**
I want there could be a function can let me choose the cluster by some feartures easily