Seafile server 7.1.0 is ready for testing! Migrate to Python 3

I tried to use seafdav with Seafile 7.1.1 on CentOS 8 but did not get it working up to now.

Missing python libraries were installed:

sudo su - seafile
pip3 install wsgidav --user
pip3 install --upgrade six>=1.13.0 --user

Log file /opt/seafile/logs/controller.log shows same error message every 10 seconds:

[01/26/20 23:17:54] seafile-controller.c(412): pid file /opt/seafile/pids/seafdav.pid does not exist
[01/26/20 23:17:54] seafile-controller.c(444): seafdav need restart…
[01/26/20 23:17:54] seafile-controller.c(79): spawn_process: /usr/bin/python3 -m wsgidav.server.server_cli --server gunicorn --root / --log-file /opt/seafile/logs/seafdav.log --pid /opt/seafile/pids/seafdav.pid --port 8080 --host 0.0.0.0 [01/26/20 23:17:54] seafile-controller.c(94): spawned /usr/bin/python3, pid 2097`

No seafdav.pid file is created. Looks like process is started and terminates immediately.

Manual start of wsgidav is not possible. I get the following error message:

/usr/bin/python3 -m wsgidav.server.server_cli --server gunicorn --root / --log-file /opt/seafile
/logs/seafdav.log --pid /opt/seafile/pids/seafdav.pid --port 8080 --host 0.0.0.0

usage: wsgidav [-h] [-p PORT] [-H HOST] [-r ROOT_PATH]
[–auth {anonymous,nt,pam-login}]
[–server {paste,gevent,cheroot,cherrypy,ext-wsgiutils,flup-fcgi,flup-fcgi_fork,wsgiref}]
[–ssl-adapter {builtin,pyopenssl}] [-v | -q]
[-c CONFIG_FILE | --no-config] [-V]
wsgidav: error: argument --server: invalid choice: ‘gunicorn’ (choose from ‘paste’, ‘gevent’, ‘cheroot’, ‘cherrypy’, ‘ext-wsgiutils’, ‘flup-fcgi’, ‘flup-fcgi_fork’, ‘wsgiref’)

wsgidav --version
3.0.2

How can I get webdav working?