Returns the gpio mode.

        gpio:= 0-53.

        Returns a value as follows

        . .
        0 = INPUT
        1 = OUTPUT
        2 = ALT5
        3 = ALT4
        4 = ALT0
        5 = ALT1
        6 = ALT2
        7 = ALT3
        . .

        ...
        print(pi.get_mode(0))
        4
        ...

def get_mode(self, gpio):
        """
        Returns the gpio mode.

        gpio:= 0-53.

        Returns a value as follows

        . .
        0 = INPUT
        1 = OUTPUT
        2 = ALT5
        3 = ALT4
        4 = ALT0
        5 = ALT1
        6 = ALT2
        7 = ALT3
        . .

        ...
        print(pi.get_mode(0))
        4
        ...
        """
        res = yield from self._pigpio_aio_command(_PI_CMD_MODEG, gpio, 0)
        return _u2i(res)