Traceback (most recent call last):
  File "/usr/bin/celery", line 11, in <module>
    sys.exit(main())
  File "/usr/lib/python3.5/site-packages/celery/__main__.py", line 30, in main
    main()
  File "/usr/lib/python3.5/site-packages/celery/bin/celery.py", line 81, in main
    cmd.execute_from_commandline(argv)
  File "/usr/lib/python3.5/site-packages/celery/bin/celery.py", line 793, in execute_from_commandline
    super(CeleryCommand, self).execute_from_commandline(argv)))
  File "/usr/lib/python3.5/site-packages/celery/bin/base.py", line 309, in execute_from_commandline
    argv = self.setup_app_from_commandline(argv)
  File "/usr/lib/python3.5/site-packages/celery/bin/base.py", line 469, in setup_app_from_commandline
    self.app = self.find_app(app)
  File "/usr/lib/python3.5/site-packages/celery/bin/base.py", line 489, in find_app
    return find_app(app, symbol_by_name=self.symbol_by_name)
  File "/usr/lib/python3.5/site-packages/celery/app/utils.py", line 235, in find_app
    sym = symbol_by_name(app, imp=imp)
  File "/usr/lib/python3.5/site-packages/celery/bin/base.py", line 492, in symbol_by_name
    return symbol_by_name(name, imp=imp)
  File "/usr/lib/python3.5/site-packages/kombu/utils/__init__.py", line 96, in symbol_by_name
    module = imp(module_name, package=package, **kwargs)
  File "/usr/lib/python3.5/site-packages/celery/utils/imports.py", line 101, in import_from_cwd
    return imp(module, package=package)
  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 "/home/michael/projects/autopool/autopool-project/autopool/__init__.py", line 4, in <module>
    from autopool.celery import app as celery_app  # noqa
  File "/home/michael/projects/autopool/autopool-project/autopool/celery.py", line 13, in <module>
    app.autodiscover_tasks(lambda: settings.INSTALLED_APPS, force=True)
  File "/usr/lib/python3.5/site-packages/celery/app/base.py", line 322, in autodiscover_tasks
    return self._autodiscover_tasks(packages, related_name)
  File "/usr/lib/python3.5/site-packages/celery/app/base.py", line 330, in _autodiscover_tasks
    self.loader.autodiscover_tasks(packages, related_name)
  File "/usr/lib/python3.5/site-packages/celery/loaders/base.py", line 252, in autodiscover_tasks
    related_name) if mod)
  File "/usr/lib/python3.5/site-packages/celery/loaders/base.py", line 273, in autodiscover_tasks
    return [find_related_module(pkg, related_name) for pkg in packages]
  File "/usr/lib/python3.5/site-packages/celery/loaders/base.py", line 273, in <listcomp>
    return [find_related_module(pkg, related_name) for pkg in packages]
  File "/usr/lib/python3.5/site-packages/celery/loaders/base.py", line 299, in find_related_module
    return importlib.import_module('{0}.{1}'.format(package, related_name))
  File "/usr/lib/python3.5/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/home/michael/projects/autopool/autopool-project/apps/pools/tasks.py", line 8, in <module>
    from .models import Period
  File "/home/michael/projects/autopool/autopool-project/apps/pools/models.py", line 14, in <module>
    from system.models import League, Team
  File "/home/michael/projects/autopool/autopool-project/apps/system/models.py", line 9, in <module>
    class Sport (models.Model):
  File "/usr/lib/python3.5/site-packages/django/db/models/base.py", line 94, in __new__
    app_config = apps.get_containing_app_config(module)
  File "/usr/lib/python3.5/site-packages/django/apps/registry.py", line 239, in get_containing_app_config
    self.check_apps_ready()
  File "/usr/lib/python3.5/site-packages/django/apps/registry.py", line 124, in check_apps_ready
    raise AppRegistryNotReady("Apps aren't loaded yet.")
django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet