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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 _redis_connection_settings(self):
 """Return a dictionary of redis connection settings. """

        return {config.HOST: self.settings.get(config.HOST, self._REDIS_HOST),
                config.PORT: self.settings.get(config.PORT, self._REDIS_PORT),
                'selected_db': self.settings.get(config.DB, self._REDIS_DB)}