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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_file_stash(self, path):
 """Stashes a file. If no root has been provided, one will be created for the directory in the user's temp directory."""

        path = os.path.normcase(path)
        head, old_head = os.path.dirname(path), None
        save_dir = None

        while head != old_head:
            try:
                save_dir = self._save_dirs[head]
                break
            except KeyError:
                pass
            head, old_head = os.path.dirname(head), head
        else:
            # Did not find any suitable root
            head = os.path.dirname(path)
            save_dir = TempDirectory(kind='uninstall')
            save_dir.create()
            self._save_dirs[head] = save_dir

        relpath = os.path.relpath(path, head)
        if relpath and relpath != os.path.curdir:
            return os.path.join(save_dir.path, relpath)
        return save_dir.path