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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 rename_file(self, old_save_name, new_save_name, new_path):
 """This only updates the name and path we use to track the file's size and upload progress. Doesn't rename it on the back end or make us upload from anywhere else. """

        if old_save_name in self._files:
            del self._files[old_save_name]
        self.update_file(new_save_name, new_path)