Proxy models are used to modify Python behaviour of a model by extending a model class. Database tables aren't generated for proxy models. So you can't use a proxy model for AUTH_USER_MODEL.

class Badge(models.Model):
    name = ...
    color = ... # gold/silver


class GoldBadge(Badge)
    class Meta:
        proxy = True

    def award(self, user):
        # award a gold badge to user

class SilverBadge(Badge):
    class Meta:
        proxy = True

    def award(self, user):
        # award a silver badge to user

Model:

cover = models.ImageField(null=True)

Template:

{% if object.cover %}
<img src="{{ object.cover.url }}"></img>
{% endif %}

Config:

MEDIA_URL = '/media/'
MEDIA_ROOT = os.path.join(BASE_DIR, '../media')

Urls:

from django.contrib.staticfiles.urls import static
from django.conf import settings
 
urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

id = models.UUIDField(primary_key=True, default=uuid4, help_text="Unique ID for this particular video")

apps.get_model('users', 'BaseUser')