text: from django.contrib.admin import AdminSite
  from django.test import TestCase
  
  from tests.example.admin import ExtraButtonExampleModelAdmin
  from tests.example.models import ExtraButtonExampleModel
  
  
  class MockRequest:
      pass
  
  
  class ExtraButtonAdminMixinUnitTest(TestCase):
      def setUp(self) -> None:
          self.site = AdminSite()
          self.request = MockRequest()
  
      def test_get_extra_button(self):
          admin = ExtraButtonExampleModelAdmin(ExtraButtonExampleModel, self.site)
          self.assertEqual(
              admin.get_extra_button(self.request),
              [
                  {
                      "label": "Example Extra Button",
                      "url": "http://example.com",
                      "class": "",
                  }
              ],
          )
  