Fix for older versions of pydantic
diff --git a/deepspeed/runtime/config_utils.py b/deepspeed/runtime/config_utils.py
index 81ef972ac0c4..08a50785ceb9 100755
--- a/deepspeed/runtime/config_utils.py
+++ b/deepspeed/runtime/config_utils.py
@@ -109,6 +109,7 @@ class Config:
         use_enum_values = True
         allow_population_by_field_name = True
         extra = "forbid"
+        arbitrary_types_allowed = True
 
 
 class pp_int(int):

resolves #2609