Cannot build container because of python-pykka dependency

[markusressel]

Hi there, I just tried to build your container using:

sudo docker build .

but I get the following error:

+ DEBIAN_FRONTEND=noninteractive apt-get install -y mopidy mopidy-soundcloud mopidy-spotify
Reading package lists...
Building dependency tree...
Reading state information...
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 mopidy : Depends: python-pykka but it is not going to be installed
 mopidy-soundcloud : Depends: python-pykka but it is not going to be installed
 mopidy-spotify : Depends: python-pykka but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
The command '/bin/sh -c set -ex  && apt-get update  && apt-get upgrade  && DEBIAN_FRONTEND=noninteractive apt-get install -y         curl         dumb-init         gcc         gnupg         gstreamer1.0-alsa         gstreamer1.0-plugins-bad         python-crypto  && curl -L https://apt.mopidy.com/mopidy.gpg | apt-key add -  && curl -L https://apt.mopidy.com/mopidy.list -o /etc/apt/sources.list.d/mopidy.list  && apt-get update  && DEBIAN_FRONTEND=noninteractive apt-get install -y         mopidy         mopidy-soundcloud         mopidy-spotify  && curl -L https://bootstrap.pypa.io/get-pip.py | python -  && pip install -U six pyasn1 requests[security] cryptography  && pip install         Mopidy-Iris         Mopidy-Moped         Mopidy-GMusic         Mopidy-Pandora         Mopidy-YouTube         pyopenssl         youtube-dl  && mkdir -p /var/lib/mopidy/.config  && ln -s /config /var/lib/mopidy/.config/mopidy  && apt-get purge --auto-remove -y         curl         gcc  && apt-get clean  && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* ~/.cache' returned a non-zero code: 100

Any clue what this is about?

[markusressel]

I changed the base image from

FROM debian:stretch-slim

to

FROM debian:buster-slim

and now it works.