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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 _save_new_defaults(self, defaults, new_version, subfolder):

 """Save new defaults"""

        new_defaults = DefaultsConfig(name='defaults-'+new_version,
                                      subfolder=subfolder)
        if not osp.isfile(new_defaults.filename()):
            new_defaults.set_defaults(defaults)
            new_defaults._save()