social_media_platform/application/admin.py

from django.contrib import admin
from django.contrib.auth import get_user_model
from django.contrib.auth.admin import UserAdmin as BaseUserAdmin
from django.contrib.auth.models import User

from .models import Post, CustomUser


class CustomUserInline(admin.StackedInline):
    model = CustomUser
    can_delete = False
    verbose_name_plural = 'customUsers'

# Define a new User admin
class UserAdmin(BaseUserAdmin):
    inlines = (CustomUserInline, )

# Re-register UserAdmin
admin.site.unregister(User)
admin.site.register(User, UserAdmin)

admin.site.register(Post)