Internal Server Error after deploy

I made a "juju deploy of the bundle":

erik@snowflake:~$ juju status
Model Controller Cloud/Region Version
website lxd-test localhost/localhost 2.1.2

App Version Status Scale Charm Store Rev OS Notes
gunicorn unknown 1 gunicorn jujucharms 9 ubuntu
postgresql unknown 1 postgresql jujucharms 62 ubuntu
python-django unknown 1 python-django jujucharms 6 ubuntu exposed

Unit Workload Agent Machine Public address Ports Message
postgresql/0* unknown idle 1 2001:16d8:ff00:8422:216:3eff:fe3c:5476 5432/tcp
python-django/0* unknown idle 0 2001:16d8:ff00:8422:216:3eff:fe18:2428 8080/tcp
  gunicorn/0* unknown idle 2001:16d8:ff00:8422:216:3eff:fe18:2428

Machine State DNS Inst id Series AZ
0 started 2001:16d8:ff00:8422:216:3eff:fe18:2428 juju-ea842e-0 precise
1 started 2001:16d8:ff00:8422:216:3eff:fe3c:5476 juju-ea842e-1 precise

Relation Provides Consumes Type
wsgi gunicorn python-django regular
replication postgresql postgresql peer
pgsql postgresql python-django regular
wsgi-file python-django gunicorn subordinate

When I try to access the website (on its IPv4 address http://192.168.1.127:8080/) I get:

"Internal Server Error"