Refs #23919 -- Removed encoding preambles and future imports

tests/db_functions/models.py

@@ -1,8 +1,6 @@
 """
 Tests for built in Function expressions.
 """
-from __future__ import unicode_literals
-
 from django.db import models
 from django.utils.encoding import python_2_unicode_compatible
 

tests/db_functions/test_datetime.py

@@ -1,5 +1,3 @@
-from __future__ import unicode_literals
-
 from datetime import datetime
 
 import pytz

tests/db_functions/tests.py

@@ -1,5 +1,3 @@
-from __future__ import unicode_literals
-
 from datetime import datetime, timedelta
 from unittest import skipIf, skipUnless