Comment ajouter un bouton qui vous redirige vers la page html django admin page

Dans mon cas, je créais un modèle pour un PDF que je voulais pouvoir prévisualiser directement à partir de la page d'administration où le modèle a été créé, afin que les gens puissent voir quel serait le résultat de l'objet qu'ils venaient de créer. J'avais vraiment besoin d'un seul lien avec une vue qui afficherait un PDF pour moi, mais même quelque chose de basique n'est pas immédiatement évident dans l'administration Django. J'ai un TransactionModelenregistré dans la adminpage comme ci-dessous:

@ admin.register(Transaction)
class TransactionAdmin(admin.ModelAdmin):
   search_fields = ['chp_reference', 'familymember__name']
   inlines = [FamilyGroupInline, FamilyMemberInline]

   def report(self, obj):
       return mark_safe(json2html.convert(json=obj.report, table_attributes="class=\"results\" 
         style=\"overflow-x:auto;\""))

   fieldsets = (
       ('Transaction Details', {
           'fields': ('chp_reference', 'income_period', 'property_market_rent', 
      'rent_effective_date', 'number_of_family_group',),
    }),
    ('Report', {
        'classes': ('collapse',),
        'fields': ('report',),
     }),
   )
    readonly_fields = ['report', 'complete', 'last_rent']

Je veux que l' Reportobjet du fieldsetssoit un lien cliquable qui redirige l'utilisateur vers un fichier html, je ne sais pas si c'est possible... et si c'est, quelle est la meilleure approche pour le faire, merci !

Voici une trace de l'erreur

    Traceback (most recent call last):
    File "C:\Users\eT3\AppData\Local\Programs\Python\Python37- 
    32\lib\threading.py", line 926, in _bootstrap_inner
    self.run()
    File "C:\Users\eT3\AppData\Local\Programs\Python\Python37- 
    32\lib\threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
    File "E:\15-12\venv\lib\site-packages\django\utils\autoreload.py", line 53, 
    in wrapper
    fn(*args, **kwargs)
    File "E:\15-12\venv\lib\site- 
    packages\django\core\management\commands\runserver.py", line 117, in 

inner_run
    self.check(display_num_errors=True)
  File "E:\15-12\venv\lib\site-packages\django\core\management\base.py", line 395, in check
    include_deployment_checks=include_deployment_checks,
  File "E:\15-12\venv\lib\site-packages\django\core\management\base.py", line 382, in _run_checks
    return checks.run_checks(**kwargs)
  File "E:\15-12\venv\lib\site-packages\django\core\checks\registry.py", line 72, in run_checks
    new_errors = check(app_configs=app_configs)
  File "E:\15-12\venv\lib\site-packages\django\core\checks\urls.py", line 13, in check_url_config
    return check_resolver(resolver)
  File "E:\15-12\venv\lib\site-packages\django\core\checks\urls.py", line 23, in check_resolver
    return check_method()
  File "E:\15-12\venv\lib\site-packages\django\urls\resolvers.py", line 407, in check
    for pattern in self.url_patterns:
  File "E:\15-12\venv\lib\site-packages\django\utils\functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "E:\15-12\venv\lib\site-packages\django\urls\resolvers.py", line 588, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "E:\15-12\venv\lib\site-packages\django\utils\functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "E:\15-12\venv\lib\site-packages\django\urls\resolvers.py", line 581, in urlconf_module
    return import_module(self.urlconf_name)
  File "C:\Users\eT3\AppData\Local\Programs\Python\Python37-32\lib\importlib\__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
  File "<frozen importlib._bootstrap>", line 983, in _find_and_load
  File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 728, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "E:\15-12\cra-calculator-master\project\urls.py", line 45, in <module>
    path('', admin.site.urls),
  File "E:\15-12\venv\lib\site-packages\django\utils\functional.py", line 225, in inner
    return func(self._wrapped, *args)
  File "E:\15-12\venv\lib\site-packages\django\contrib\admin\sites.py", line 293, in urls
    return self.get_urls(), 'admin', self.name
  File "E:\15-12\venv\lib\site-packages\django\contrib\admin\sites.py", line 277, in get_urls
    path('%s/%s/' % (model._meta.app_label, model._meta.model_name), include(model_admin.urls)),
  File "E:\15-12\venv\lib\site-packages\django\contrib\admin\options.py", line 628, in urls
    return self.get_urls()
  File "E:\15-12\cra-calculator-master\app\admin.py", line 145, in get_urls
    urls += pattern
TypeError: 'URLPattern' object is not iterable

Voici mon preview_pdf_view()

def preview_pdf_view(self, request, **kwargs):
    tx = Transaction.objects.get(id=kwargs['id'])
    context = {'tx': tx}
    return TemplateResponse(request, 'admin/preview_pdf.html', context=context)

get_url()

def get_urls(self):
    urls = super().get_urls()
    pattern = path('preview/<int:id>/', self.admin_site.admin_view(self.preview_pdf_view), name='preview-pdf')
    urls += pattern
    return urls

et dans le models.pyj'ai ajoutépreview_link()

@property
    def preview_link(self):
        a = '''<a href=" url 'preview-pdf' id={} , name={}"</a>'''.format(self.id, self.chp_reference)
        return mark_safe(a)