def _get_serial_number(self):
        """
        Retrieves the FTDI device serial number.

        :returns: string containing the device serial number
        """
        return usb.util.get_string(self._device.usb_dev, 64, self._device.usb_dev.iSerialNumber)
def _get_serial_number ( self ) : return usb . util . get_string ( self . _device . usb_dev , 64 , self . _device . usb_dev . iSerialNumber )
Retrieves the FTDI device serial number.

        :returns: string containing the device serial number