diff --git a/openai/api_requestor.py b/openai/api_requestor.py
index 827b73b78e..a56e16c417 100644
--- a/openai/api_requestor.py
+++ b/openai/api_requestor.py
@@ -667,7 +667,7 @@ def _interpret_response_line(
                 headers=rheaders,
             )
         try:
-            if 'text/plain' in rheaders.get('Content-Type'):
+            if 'text/plain' in rheaders.get('Content-Type', ''):
                 data = rbody
             else:
                 data = json.loads(rbody)