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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 create_unique_autosave_filename(self, filename, autosave_dir):
 """ Create unique autosave file name for specified file name. Args: filename (str):
 original file name autosave_dir (str):
 directory in which autosave files are stored """

        basename = osp.basename(filename)
        autosave_filename = osp.join(autosave_dir, basename)
        if autosave_filename in self.name_mapping.values():
            counter = 0
            root, ext = osp.splitext(basename)
            while autosave_filename in self.name_mapping.values():
                counter += 1
                autosave_basename = '{}-{}{}'.format(root, counter, ext)
                autosave_filename = osp.join(autosave_dir, autosave_basename)
        return autosave_filename