Image is null after its picked by using image_picker package and saved on local memory (flutter) - flutter

Question

Description:
I'm using (image_picker: ^0.8.5+3) package to pick the images from gallery and camera and then upload them on backend server (django by using django rest framework)
Issue:
Image is getting null outside picker function, even though state has been set by using setSatet(() {}) method
Failed Solutions:
I tried to save the image locally before uploading the image on the backend, But image still shown null once its used or referenced outside picker function
Note: backend API's works fine and i can upload images by using postman
picker function:
// Get image from gallery and store it locally
Future<File?> _getFromGallery() async {
PickedFile? image = await ImagePicker.platform.pickImage(source: ImageSource.gallery);
if (image == null) {
return null;
}
final File file = File(image.path);
final Directory directory = await getApplicationDocumentsDirectory();
final imagepath = directory.path;
final String fileName = path.basename(image.path);
File newImage = await file.copy('$imagepath/$fileName');
setState(() {
_imagelocal = newImage;
print('image.path1');
print(_imagelocal!.path);
});
}
Uploading image function:
_uploadimage() async {
Map<String,String> header = {
"Content-Type":"application/octet-stream)"
};
print("uploaded image invoked");
var request = http.MultipartRequest('POST', Uri.parse('http://192.168.1.15:8000/api/uploadimage'));
// request.files.add(await http.MultipartFile('image',http.ByteStream(image.openRead()).cast(),await image.length(),filename:image.name, contentType: MediaType('image', 'jpg')));
request.files.add(await http.MultipartFile('LoadModelImage',http.ByteStream(_imagelocal!.openRead()).cast(),await _imagelocal!.length(),));
request.headers.addAll(header);
//for completeing the request
var response =await request.send();
//for getting and decoding the response into json format
var responsed = await http.Response.fromStream(response);
final responseData = json.decode(responsed.body);
if (response.statusCode==201) {
print("SUCCESS");
print(responseData);
}
else {
print("ERROR");
}
}