expected str, bytes or os.PathLike object, not InMemoryUploadedFile

The error is happening because the function handle_uploaded_file(f) is trying to open an already opened file.

The value of request.FILES['file'] is a InMemoryUploadedFile and can be used like a normal file. You don't need to open it again.

To fix, just remove the line that tries to open the file:

def handle_uploaded_file(f):
    for x in f:
        if x.startswith('newick;'):
            print('')
    return cutFile(x)