text: import unittest
  from unittest import mock
  from title_ui.main import app
  from title_ui.custom_extensions.security_headers.main import SecurityHeaders
  
  
  class TestSecurityHeaders(unittest.TestCase):
  
      def setup_method(self, method):
          self.app = app.test_client()
  
      @mock.patch('title_ui.custom_extensions.security_headers.main.SecurityHeaders.init_app')
      def test_extension_alternative_init(self, mock_init_app):
          SecurityHeaders('foo')
          mock_init_app.assert_called_once_with('foo')
  
      def test_headers_present(self):
          response = self.app.get('/')
  
          expected_headers = [
              'X-Frame-Options',
              'Strict-Transport-Security',
              'X-XSS-Protection',
              'X-Content-Type-Options'
          ]
  
          for header in expected_headers:
              self.assertIn(header, response.headers)
  