Hass.io error while connecting to IKEA Tradfri gateway

I have upgraded to 0.57.1 and get APIFacory errors.
Looks like something isn’t installed! Traceback (most recent call last): File “/usr/lib/python3.6/site-packages/homeassistant/components/tradfri.py”, line 60, in configuration_callback from pytradfri.api.aiocoap_api import APIFactory