Django rest framework response : "The submitted data was not a file. Check the encoding type on the form."

I made minimal working code for test it and it seems problem makes .dict() in

requestdata = request.data.dict()

{'filelist': }

but code needs list (even if there is only one file) - like this

{'filelist': [, ]}

requestdata = request.data

or I use standard dict(...) if you really need standard dict instead of QueryDict

requestdata = dict(request.data)
{'filelist': [, ]}>

Works also with requests.FILES

requestdata = {"filelist": request.FILES.getlist("filelist")}

filelist = data.get("filelist")
uploadedfiles = data.pop(filelist)

It has to be string "filelist" instead of variable filelist

# no need to use data.get()
uploadedfiles = data.pop("filelist")

class PostImageValidate(APIView):
    # permissionclasses = (IsAuthenticated, IsNotSuspended)
    def put(self, request):
        print("\n=== put ===\n")
        print("=== request.data ===")
        print(request.data)
        print("=== request.data.dict() ===")
        print(request.data.dict())
        print("=== request.data.lists() ===")
        print(request.data.lists())
        print(list(request.data.lists()))
        print("=== dict(request.data) ===")
        print(dict(request.data))
        print('=== request.FILES.getlist("filelist") ===')
        print(request.FILES.getlist("filelist"))
        # requestdata = request.data.dict()   # WRONG
        # requestdata = dict(request.data)
        requestdata = request.data
        # requestdata = {"filelist": request.FILES.getlist("filelist")}
        print("=== requestdata ===")
        print(requestdata)
        serializer = TempImageSerializer(data=requestdata)
        serializer.isvalid(raiseexception=True)
        data = serializer.validateddata
        # uploadedfiles = data.pop("filelist")
        uploadedfiles = data.get("filelist")
        print("=== uploadedfiles ===")
        print(uploadedfiles)
        results = []
        for file in uploadedfiles:
            results.append(
                {"filename": file.name, "size": file.size, "status": "Processed"}
            )
        output = {
            "message": "Images processed successfully",
            "results": results,
            "number of items": len(results),
        }
        return Response(output, status=status.HTTP201CREATED)

curl -X PUT \
  -F "filelist=@lenna.jpg" \
  -F "file_list=@lenna.png" \
  -F "other=Hello World!" \
  http://127.0.0.1:8000/api/upload/