bug fixes
diff --git a/plstackapi/core/api/slice_memberships.py b/plstackapi/core/api/slice_memberships.py
index 54a1cba..431552d 100644
--- a/plstackapi/core/api/slice_memberships.py
+++ b/plstackapi/core/api/slice_memberships.py
@@ -2,7 +2,7 @@
 from plstackapi.openstack.client import OpenStackClient
 from plstackapi.openstack.driver import OpenStackDriver
 from plstackapi.core.api.auth import auth_check
-from plstackapi.core.models import SliceMembership, Slice, Role, User
+from plstackapi.core.models import SliceMembership
 from plstackapi.core.api.users import _get_users
 from plstackapi.core.api.slices import _get_slices
 from plstackapi.core.api.roles import _get_roles