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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 touched(self):
 """Return touch state of all pins as a 12-bit value where each bit represents a pin, with a value of 1 being touched and 0 not being touched. """

        t = self._i2c_retry(self._device.readU16LE, MPR121_TOUCHSTATUS_L)
        return t & 0x0FFF