Update pmoe.py

Author: quantumiracle

pmoe.py

@@ -1,6 +1,9 @@
 '''
 Probabilistic Mixture-of-Experts
 paper: https://arxiv.org/abs/2104.09122
+
+Core features:
+It replaces the diagonal Gaussian distribution with (differentiable) Gaussian mixture model for policy function approximation, which is more expressive.
 '''
 
 import argparse