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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 _config(self):
 """Value to be written to the device's config register """

        config = 0
        if self.mode == MODE_NORMAL:
            config += (self._t_standby << 5)
        if self._iir_filter:
            config += (self._iir_filter << 2)
        return config