How to Get points coords with actor

I have a dataset, points and cells are origin from this dataset. Not all dataset poins are used, How can i get coords of all used points on prob(actor) directly? just like paraview 5.8.0 function: selecte points on

cell id max may over 50000000, the following methold is slow on python:
for (id=0,id++,id<cell id max)