import asyncio
from bleak import BleakClient

uuid = "F451470C-..."
svc  = "19b10001-e8f2-537e-4f6c-d104768a1217"

async def press_button(x, y, z):
    async with BleakClient(uuid) as c:
        await c.write_gatt_char(svc, bytes([x]))
        await c.write_gatt_char(svc, bytes([y]))
        await c.write_gatt_char(svc, bytes([z]))

asyncio.run(press_button(20, 20, 35))