Django-cms: 'Settings' object has no attribute 'SITE_ID' - django

Question

I would like to enable my django-cms instance to host multiple sites.
For that I created two different sites in the admin panel.
Unfortunately only one site is shown because I needed to hardcode the SITE_ID in the project settings.
According to https://github.com/django/django/pull/2460 this is not a mandatory setting anymore. But my Django 1.10.7 instance shows the following traceback if I delete it:
Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/var/www/venv/lib/python3.5/site-packages/django/core/management/__init__.py", line 338, in execute_from_command_line
utility.execute()
File "/var/www/venv/lib/python3.5/site-packages/django/core/management/__init__.py", line 312, in execute
django.setup()
File "/var/www/venv/lib/python3.5/site-packages/django/__init__.py", line 18, in setup
apps.populate(settings.INSTALLED_APPS)
File "/var/www/venv/lib/python3.5/site-packages/django/apps/registry.py", line 115, in populate
app_config.ready()
File "/var/www/venv/lib/python3.5/site-packages/django/contrib/admin/apps.py", line 22, in ready
self.module.autodiscover()
File "/var/www/venv/lib/python3.5/site-packages/django/contrib/admin/__init__.py", line 24, in autodiscover
autodiscover_modules('admin', register_to=site)
File "/var/www/venv/lib/python3.5/site-packages/django/utils/module_loading.py", line 74, in autodiscover_modules
import_module('%s.%s' % (app_config.name, module_to_search))
File "/usr/lib/python3.5/importlib/__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 986, in _gcd_import
File "<frozen importlib._bootstrap>", line 969, in _find_and_load
File "<frozen importlib._bootstrap>", line 958, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 673, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 665, in exec_module
File "<frozen importlib._bootstrap>", line 222, in _call_with_frames_removed
File "/var/www/venv/lib/python3.5/site-packages/cms/admin/__init__.py", line 2, in <module>
import cms.admin.pageadmin
File "/var/www/venv/lib/python3.5/site-packages/cms/admin/pageadmin.py", line 39, in <module>
from cms.admin.forms import (
File "/var/www/venv/lib/python3.5/site-packages/cms/admin/forms.py", line 85, in <module>
class PageForm(forms.ModelForm):
File "/var/www/venv/lib/python3.5/site-packages/cms/admin/forms.py", line 86, in PageForm
language = forms.ChoiceField(label=_("Language"), choices=get_language_tuple(),
File "/var/www/venv/lib/python3.5/site-packages/cms/utils/i18n.py", line 76, in get_language_tuple
return [(lang['code'], lang['name']) for lang in get_languages(site_id)]
File "/var/www/venv/lib/python3.5/site-packages/cms/utils/i18n.py", line 23, in get_languages
site_id = get_site_id(site_id)
File "/var/www/venv/lib/python3.5/site-packages/cms/utils/conf.py", line 294, in get_site_id
return settings.SITE_ID
File "/var/www/venv/lib/python3.5/site-packages/django/conf/__init__.py", line 49, in __getattr__
return getattr(self._wrapped, name)
AttributeError: 'Settings' object has no attribute 'SITE_ID'

Answer 1

Looks like SITE_ID is required by Django CMS, it's in the traceback
File "/var/www/venv/lib/python3.5/site-packages/cms/utils/conf.py", line 294, in get_site_id
return settings.SITE_ID

Answer 2

I solved to problem differently.
I used the plugin djangocms-multisite.
I don't know if it is the best solution but it works.