Наследование InlineModelAdmin в Django admin.py

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from django.contrib.auth.models import User

from .models import UserInfo, PhotoAlbum, Photos

class PhotosInfoLine(admin.StackedInline):
    model = Photos
    can_delete = False
    verbose_name_plural = 'Photos'

class PhotoAlbumInfoLine(admin.StackedInline):
    model = PhotoAlbum
    can_delete = False
    verbose_name_plural = 'PhotoAlbum'


class UserInfoInline(admin.StackedInline):
    model = UserInfo
    fields = ('id', 'imgUrl', 'head', 'descr', 'age', 'gender', 'interests', 'status', 'is_blocked', 'reason_of_blocking', 'is_deleted')
    can_delete = False
    verbose_name_plural = 'UserInfo'


class UserAdminIL(UserAdmin):
    list_display = ('username','id', 'first_name', 'last_name', 'email' , 'date_joined', 'last_login', 'is_active')
    fieldsets = (
        (None, {
            'fields': ('username', 'first_name', 'last_name', 'email', 'date_joined', 'last_login', 'is_active'),
        }),
    )
    readonly_fields = ('date_joined', 'last_login', 'id',)
    list_filter = ('date_joined', 'last_login')

    ordering = ('-date_joined',)
    inlines = (UserInfoInline, )


admin.site.unregister(User)
admin.site.register(User, UserAdminIL)