diff --git a/ldapcherry/backend/backendAD.py b/ldapcherry/backend/backendAD.py
index 6feb890..e59ca8c 100644
--- a/ldapcherry/backend/backendAD.py
+++ b/ldapcherry/backend/backendAD.py
@@ -139,6 +139,7 @@ class Backend(ldapcherry.backend.backendLdap.Backend):
             }
 
         self.attrlist = []
+        self.group_attrs_keys = []
         for a in attrslist:
             self.attrlist.append(self._str(a))
 
diff --git a/ldapcherry/backend/backendLdap.py b/ldapcherry/backend/backendLdap.py
index 1edffbe..c36ba9f 100644
--- a/ldapcherry/backend/backendLdap.py
+++ b/ldapcherry/backend/backendLdap.py
@@ -180,7 +180,6 @@ class Backend(ldapcherry.backend.Backend):
         or if it's multivaluated.
         """
         for key in self.group_attrs_keys:
-            pass
             if key not in attrs:
                 raise MissingGroupAttr(key)
             if type(attrs[key]) is list and len(attrs[key]) == 1: