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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 begin(self):
 """Initialize communication with the PN532. Must be called before any other calls are made against the PN532. """

        # Assert CS pin low for a second for PN532 to be ready.
        self._gpio.set_low(self._cs)
        time.sleep(1.0)
        # Call GetFirmwareVersion to sync up with the PN532.  This might not be
        # required but is done in the Arduino library and kept for consistency.
        self.get_firmware_version()
        self._gpio.set_high(self._cs)