What object are you referring to? PyRosetta uses the Pose object exclusively and PDB file format for input/output. It wouldn’t be too hard to write a Python object that takes in a Pose object however and can interface with PyMol.
We’re still working on integrating PyRosetta with Pymol. There is a script called “PyRosetta-Pymol.py” in the pyrosetta directory which starts to address the issue. If you want to tackle the problem, try starting with that.