diff --git a/litellm/llms/anthropic.py b/litellm/llms/anthropic.py
index 7a2b3d8d84..8cce80826b 100644
--- a/litellm/llms/anthropic.py
+++ b/litellm/llms/anthropic.py
@@ -164,11 +164,9 @@ def completion(
 
         model_response["created"] = time.time()
         model_response["model"] = model
-        model_response["usage"] = {
-            "prompt_tokens": prompt_tokens,
-            "completion_tokens": completion_tokens,
-            "total_tokens": prompt_tokens + completion_tokens,
-        }
+        model_response.usage.completion_tokens = completion_tokens
+        model_response.usage.prompt_tokens = prompt_tokens
+        model_response.usage.total_tokens = prompt_tokens + completion_tokens
         return model_response
 
 def embedding():