How to parse a complete dos object from DOSCAR but not from vasprun.xml by pymatgen

Hello dear,
I have some trouble when I parse a DOS object with vasprun.xml obtained from GW calculation. The error is as follows:
“NotImplementedError: This vasprun.xml has >2 unlabelled dielectric functions”
So I want to parse it by using DOSCAR instead of the vasprun.xml. But I have not found a class that can do this in pymatgen. If anyone can help me write a new class or some other advices in pymatgen, I will be super grateful to you. Thanks.