fix(types/utils.py): support openai 'file' message type

Closes https://github.com/BerriAI/litellm/issues/9365

litellm/types/llms/openai.py

@@ -436,12 +436,24 @@ class ChatCompletionDocumentObject(TypedDict):
     citations: Optional[CitationsObject]
 
 
+class ChatCompletionFileObjectFile(TypedDict):
+    file_data: Optional[str]
+    file_id: Optional[str]
+    filename: Optional[str]
+
+
+class ChatCompletionFileObject(TypedDict):
+    type: Literal["file"]
+    file: ChatCompletionFileObjectFile
+
+
 OpenAIMessageContentListBlock = Union[
     ChatCompletionTextObject,
     ChatCompletionImageObject,
     ChatCompletionAudioObject,
     ChatCompletionDocumentObject,
     ChatCompletionVideoObject,
+    ChatCompletionFileObject,
 ]
 
 OpenAIMessageContent = Union[
@@ -523,6 +535,7 @@ ValidUserMessageContentTypes = [
     "input_audio",
     "document",
     "video_url",
+    "file",
 ]  # used for validating user messages. Prevent users from accidentally sending anthropic messages.
 
 AllMessageValues = Union[

tests/litellm_utils_tests/test_utils.py

@@ -1094,6 +1094,26 @@ def test_is_base64_encoded_2():
     [
         ([{"role": "user", "content": "hi"}], True),
         ([{"role": "user", "content": [{"type": "text", "text": "hi"}]}], True),
+        (
+            [
+                {
+                    "role": "user",
+                    "content": [
+                        {
+                            "type": "file",
+                            "file": {
+                                "file_id": "123",
+                                "file_name": "test.txt",
+                                "file_size": 100,
+                                "file_type": "text/plain",
+                                "file_url": "https://example.com/test.txt",
+                            },
+                        }
+                    ],
+                }
+            ],
+            True,
+        ),
         (
             [
                 {