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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:
 async def pixy_init(self, max_blocks=5, cb=None, cb_type=None):
 """ Initialize Pixy and enable Pixy block reporting. This is a FirmataPlusRB feature. :param cb: callback function to report Pixy blocks :param cb_type: Constants.CB_TYPE_DIRECT = direct call or Constants.CB_TYPE_ASYNCIO = asyncio coroutine :param max_blocks: Maximum number of Pixy blocks to report when many signatures are found. :returns: No return value. """

        if cb:
            self.digital_pins[PrivateConstants.PIN_PIXY_MOSI].cb = cb  # Pixy uses SPI.  Pin 11 is MOSI.
        if cb_type:
            self.digital_pins[PrivateConstants.PIN_PIXY_MOSI].cb_type = cb_type
        data = [PrivateConstants.PIXY_INIT, max_blocks & 0x7f]
        await self._send_sysex(PrivateConstants.PIXY_CONFIG, data)