asyncio.Queue to process SenseHat keyboard events in asynchronous event loop

sample.py

#!/usr/bin/python
import asyncio
from sense_hat import SenseHat

sense: SenseHat = None
loop: asyncio.AbstractEventLoop = None
queue: asyncio.Queue = None


def process_direction(event):
    """ sychronous code executed on main thread
    """
    if event.action == 'pressed':
        direction = event.direction
        asyncio.run_coroutine_threadsafe(queue.put(direction), loop=loop)


async def show(direction):
    """ asynchronous code executed on the event loop
    """
    if direction == 'up':
        sense.show_letter("U")
    elif direction == "down":
        sense.show_letter("D")
    elif direction == "left":
        sense.show_letter("L")
    elif direction == "right":
        sense.show_letter("R")
    elif direction == "middle":
        sense.show_letter("M")


async def main():
    global loop
    global queue
    loop = asyncio.get_event_loop()
    queue = asyncio.Queue()
    while True:
        direction = await queue.get()
        await show(direction)
        queue.task_done()
        if queue.empty():
            await asyncio.sleep(.5)
        sense.clear()

try:
    sense = SenseHat()
    sense.clear()
    sense.stick.direction_any = process_direction
    asyncio.run(main())
except Exception as ex:
    print(ex)