After I added readonly_fields, the server stopped starting, what should I do?

Question

Django

Good evening!
I'm learning how to build a website with Django. I decided to customize the admin panel a bit. After I wrote the readonly_fields line in the admin.py tab and ran the python manage.py runserver command, I got an error:

Exception in thread django-main-thread:
Traceback (most recent call last):
  File "C:\Program Files (x86)\Python\lib\threading.py", line 932, in _bootstrap_inner
    self.run()
  File "C:\Program Files (x86)\Python\lib\threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "D:\django sites\testsite\venv\lib\site-packages\django\utils\autoreload.py", line 53, in wrapper
    fn(*args, **kwargs)
  File "D:\django sites\testsite\venv\lib\site-packages\django\core\management\commands\runserver.py", line 11
8, in inner_run
    self.check(display_num_errors=True)
  File "D:\django sites\testsite\venv\lib\site-packages\django\core\management\base.py", line 442, in check
    raise SystemCheckError(msg)
django.core.management.base.SystemCheckError: SystemCheckError: System check identified some issues:

ERRORS:
<class 'news.admin.NewsAdmin'>: (admin.E035) The value of 'readonly_fields[1]' is not a callable, an attribute
 of 'NewsAdmin', or an attribute of 'news.News'.
System check identified 1 issue (0 silenced).

admin.py

from django.contrib import admin
from django.utils.safestring import mark_safe

from .models import News, Category


class NewsAdmin(admin.ModelAdmin):
    list_display = ('id', 'title', 'category', 'created_at', 'updated_at', 'is_published', 'get_photo')
    list_display_links = ('id', 'title')
    search_fields = ('title', 'content')
    list_editable = ('is_published',)
    list_filter = ('is_published', 'category')
    fields = ('title', 'category', 'content', 'photo', 'get_photo', 'is_published', 'views', 'created_at', 'updated_at')
    readonly_fields = ('get_photo', 'views', 'created_at', 'updated_at')
    save_on_top = True

    def get_photo(self, obj):
        if obj.photo:
            return mark_safe(f'<img src="{obj.photo.url}" width="75">')
        else:
            return '-'

    get_photo.short_description = 'Миниатюра'

class CategoryAdmin(admin.ModelAdmin):
    list_display = ('id', 'title')
    list_display_links = ('id', 'title')
    search_fields = ('title',)


admin.site.register(News, NewsAdmin)
admin.site.register(Category, CategoryAdmin)

admin.site.site_title = 'Управление новостями'
admin.site.site_header = 'Управление новостями'

Please help me find a solution to the problem

Answer 1

Does your News model have a views field ?