enable notification BLE (PyCharm)

Question

i tried to notify the device but the problem is that nothing is printed in my console when using this function:

def callback(sender: int, data: bytearray):                                                                           
    print("{0}: {1}".format(sender, data))

in the main program i used start_notify method

await client.start_notify(chrc, callback)

I'm asking, does anybody have a idea how to print the data