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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 voltage(self):
 """Returns the voltage from the ADC pin as a floating point value."""

        raw = self.value
        volts = raw * (_ADS1X15_PGA_RANGE[self._ads.gain] / (2**(self._ads.bits-1) - 1))
        return volts