bleak.exc.BleakError: Characteristic was not found!

• bleak version: 0.9.1 / 0.8.0
• Python version: 3.8.6 / 3.8.4
• Operating System: Windows 10 / Debian 10 (RPi3b+)
• BlueZ: bluetoothctl: 5.50

Description

I’m trying to connect to a BLE device via bleak - it works fine when I use my script on Windows 10, but the same script fails on Linux:

bleak.exc.BleakError: Characteristic 11111111-1111-1111-1111-111111111111 was not found!

What I Did

My code:

from bleak import BleakClient
import asyncio


address = "xx:xx:xx:xx:xx:xx"
ble_uuid = "11111111-1111-1111-1111-111111111111"

msg = b'ABC'
async def run(address, loop):
        async with BleakClient(address, loop=loop) as client:
            await client.write_gatt_char(ble_uuid, msg, True)

loop = asyncio.get_event_loop()
loop.run_until_complete(run(address, loop))

The difference I see is a different bleak version on Win and on Linux. On Linux pip3 install bleak returns only bleak 0,8.0:

pip3 install bleak
Defaulting to user installation because normal site-packages is not writeable
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: bleak in /home/pi/.local/lib/python3.8/site-packages (0.8.0)

Traceback (most recent call last):
  File "script.py", line 13, in <module>
    loop.run_until_complete(run(address, loop))
  File "/usr/local/lib/python3.8/asyncio/base_events.py", line 616, in run_until_complete
    return future.result()
  File "script.py", line 11, in run
    await client.write_gatt_char(ble_uuid, msg, True)
  File "/home/pi/.local/lib/python3.8/site-packages/bleak/backends/bluezdbus/client.py", line 580, in write_gatt_char
    raise BleakError("Characteristic {0} was not found!".format(char_specifier))
bleak.exc.BleakError: Characteristic 11111111-1111-1111-1111-111111111111 was not found!