fix imports, travis error

rest_framework/validators.py

@@ -6,9 +6,9 @@ This gives us better separation of concerns, allows us to use single-step
 object creation, and makes it possible to switch between using the implicit
 `ModelSerializer` class and an equivalent explicit `Serializer` class.
 """
+from django.contrib.auth import password_validation
 from django.db import DataError
 from django.utils.translation import gettext_lazy as _
-from django.contrib.auth import password_validation
 
 from rest_framework.exceptions import ValidationError
 from rest_framework.utils.representation import smart_repr

tests/test_validators.py

@@ -1,15 +1,15 @@
 import datetime
 
 import pytest
+from django.contrib.auth import password_validation
 from django.db import DataError, models
 from django.test import TestCase
-from django.contrib.auth import password_validation
 
 from rest_framework import serializers
 from rest_framework.exceptions import ValidationError
 from rest_framework.validators import (
-    BaseUniqueForValidator, UniqueTogetherValidator, UniqueValidator,
-    qs_exists, PasswordValidator
+    BaseUniqueForValidator, PasswordValidator, UniqueTogetherValidator,
+    UniqueValidator, qs_exists
 )