When successfully subscribing to a web socket, the event subscribed is never received

[funnel20]

Using Python SDK version 1.4.2 I follow the simple documentation at https://docs.bitvavo.com/#tag/Market-data-subscription-WebSocket/paths/~1subscribeTicker/post to subscribe to a ticker via code:

from python_bitvavo_api.bitvavo import Bitvavo

def callback(response):
  print("Callback:", json.dumps(response, indent=2))

def errorCallback(error):
  print("Error callback:", json.dumps(error, indent=2))

bitvavo = Bitvavo()
websocket = bitvavo.newWebsocket()
websocket.setErrorCallback(errorCallback)

websocket.subscriptionTicker('BTC-EUR', callback)

According to the docu, the subscription should be confirmed by a positive response:

{
  "event": "subscribed",
  "subscriptions": {
    "ticker": [
      "BTC-EUR"
    ]
  }
}

However, this is never received, only positive ticker responses.

The same applies to Candles subscription at https://docs.bitvavo.com/#tag/Market-data-subscription-WebSocket/paths/~1subscribeCandles/post

It seems that the subscribed event is not send by the server, or ignored by the SDK.

Please implement the subscription confirmation, so we can add proper fault handling in our application.