diff --git a/apps/assets/api/admin_user.py b/apps/assets/api/admin_user.py
index c77da1ae4..3780def5e 100644
--- a/apps/assets/api/admin_user.py
+++ b/apps/assets/api/admin_user.py
@@ -1,17 +1,4 @@
-# ~*~ coding: utf-8 ~*~
-# Copyright (C) 2014-2018 Beijing DuiZhan Technology Co.,Ltd. All Rights Reserved.
-#
-# Licensed under the GNU General Public License v2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.gnu.org/licenses/gpl-2.0.html
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
+
 
 from django.db import transaction
 from django.db.models import Count
diff --git a/apps/users/serializers/user.py b/apps/users/serializers/user.py
index f4c2ee085..c961cccb4 100644
--- a/apps/users/serializers/user.py
+++ b/apps/users/serializers/user.py
@@ -30,7 +30,7 @@ class UserSerializer(BulkSerializerMixin, serializers.ModelSerializer):
         (1, CUSTOM_PASSWORD)
     )
     password_strategy = serializers.ChoiceField(
-        choices=PASSWORD_STRATEGY_CHOICES, required=True, initial=0,
+        choices=PASSWORD_STRATEGY_CHOICES, required=False, initial=0,
         label=_('Password strategy'), write_only=True
     )
 
@@ -62,9 +62,9 @@ class UserSerializer(BulkSerializerMixin, serializers.ModelSerializer):
 
     def set_role_choices(self):
         role = self.fields['role']
-        choices = role.choices
+        choices = role._choices
         choices.pop('App', None)
-        role.choices = choices
+        role._choices = choices
 
     def validate_role(self, value):
         request = self.context.get('request')