[DOC] improve docstring for Optimizer.state_dict (#63153)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63153

Fixes: https://github.com/pytorch/pytorch/issues/60121

Test Plan: Imported from OSS

Reviewed By: pbelevich

Differential Revision: D30629462

Pulled By: tugsbayasgalan

fbshipit-source-id: a9160e02ac53bb1a6219879747d73aae9ebe4d2f

diff --git a/torch/optim/optimizer.py b/torch/optim/optimizer.py
index 02f1cc2..79f72f0 100644 (file)
--- a/torch/optim/optimizer.py
+++ b/torch/optim/optimizer.py
@@ -100,7 +100,8 @@ class Optimizer(object):
 
         * state - a dict holding current optimization state. Its content
             differs between optimizer classes.
-        * param_groups - a dict containing all parameter groups
+        * param_groups - a list containing all parameter groups where each
+            parameter group is a dict
         """
         # Save order indices instead of Tensors
         param_mappings = {}