For the tests listed bellow, those tests are trying to access

web_site_module from self object. Tests:
test_03_WebSection_getDocumentValueListSecurity
test_04_ExpireUserAction
test_05_createWebSite
test_06_createWebSection
test_WebSiteModuleDefaultSecurity
test_getDocumentValueList_AnonymousUser

product/ERP5/tests/testERP5Web.py

@@ -1369,6 +1369,7 @@ class TestERP5WebWithSimpleSecurity(ERP5TypeTestCase):
     user_folder._doAddUser(name, 'password', role_list, [])
 
   def afterSetUp(self):
+    self.web_site_module = self.portal.web_site_module
     self.portal.Localizer = DummyLocalizer()
     self.createUser('admin', ['Manager'])
     self.createUser('erp5user', ['Auditor', 'Author'])