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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 clean_weight_files(cls):
 """ Cleans existing weight files. """

        deleted = []
        for f in cls._files:
            try:
                os.remove(f)
                deleted.append(f)
            except FileNotFoundError:
                pass
        print('Deleted %d weight files' % len(deleted))
        cls._files = []