fix mypy error

Author: zainhas

src/together/types/chat_completions.py

@@ -70,17 +70,17 @@ class ChatCompletionMessage(BaseModel):
 
 
 class ResponseFormat(BaseModel):
-    type: ResponseFormatType
-    schema_: Dict[str, Any] | None = None
-    pattern: str | None = None
-    
-    def to_dict(self) -> Dict[str, Any]:
-        result = {"type": self.type}
-        if self.schema_ is not None:
-            result["schema"] = self.schema_
-        if self.pattern is not None:
-            result["pattern"] = self.pattern
-        return result
+   type: ResponseFormatType
+   schema_: Dict[str, Any] | None = None
+   pattern: str | None = None
+
+   def to_dict(self) -> Dict[str, Any]:
+       result: Dict[str, Any] = {"type": self.type.value}
+       if self.schema_ is not None:
+           result["schema"] = self.schema_
+       if self.pattern is not None:
+           result["pattern"] = self.pattern
+       return result
 
 
 class FunctionTool(BaseModel):