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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 quality_to_apply(self):
 """Value of quality parameter to use in processing request. Simple substitution of 'native' or 'default' if no quality parameter is specified. """

        if (self.request.quality is None):
            if (self.api_version <= '1.1'):
                return('native')
            else:
                return('default')
        return(self.request.quality)