Custom User and Group Model Issue

There are several issues with your custom User and Group model implementation that are causing the permission-related methods to fail.

Main Issues

1. Missing PermissionsMixin: Your User class extends AbstractUser but your custom Group model doesn't properly integrate with Django's permission system.

2. Incorrect string literals: You're using "_('name')" instead of _("name") for translations.

3. Missing import: The _ function for translations isn't imported.

4. Incorrect settings configuration: AUTH_GROUP_MODEL is not a standard Django setting.

Corrected Implementation

Here's how you should fix your models:

PYTHONCopied
# models.py (myusers app)
from django.db import models
from django.contrib.auth.models import AbstractUser, GroupManager, Permission, PermissionsMixin
from django.utils.translation import gettext_lazy as _

class AbstractGroup(models.Model):
    name = models.CharField(_('name'), max_length=150, unique=True)
    permissions = models.ManyToManyField(
        Permission,
        verbose_name=_('permissions'),
        blank=True,
        related_name="fk_group_permission",
    )

    objects = GroupManager()

    def __str__(self):
        return self.name

    def natural_key(self):
        return (self.name,) 

    class Meta:
        verbose_name = _('group')
        verbose_name_plural = _('groups')
        abstract = True

class Group(AbstractGroup):
    is_active = models.BooleanField(_('Is Active'), default=True)

class User(AbstractUser, PermissionsMixin):
    groups = models.ManyToManyField(
        Group,
        verbose_name=_('groups'),
        blank=True,
        help_text=_(
            "The groups this user belongs to. A user will get all permissions "
            "granted to each of their groups."
        ),
        related_name="user_set",
        related_query_name="user",
    )

And in settings.py:

PYTHONCopied
AUTH_USER_MODEL = 'myusers.User'
# Remove AUTH_GROUP_MODEL as it's not a standard Django setting

Important Notes

1. PermissionsMixin: Although AbstractUser already includes PermissionsMixin, I've explicitly included it to highlight its importance. The PermissionsMixin provides the methods like get_all_permissions() and get_group_permissions().

2. Custom Group Model: Django doesn't have a built-in setting like AUTH_GROUP_MODEL. When you customize the Group model, you need to ensure your User model correctly references it, which you've done with the groups field.

3. Translation Strings: The correct syntax for translation strings is _("text"), not "_('text')".

4. Permissions Handling: When you customize both User and Group models, you need to ensure the permission-related methods in PermissionsMixin can properly work with your custom Group model.

The error you're seeing suggests that Django's permission methods are trying to query against the built-in Group model rather than your custom one, which indicates an issue with how the models are connected in the authentication backend.