Removed unused imports.

django/core/management/commands/sendtestemail.py

@@ -2,7 +2,7 @@ import datetime
 import socket
 
 from django.core.mail import send_mail
-from django.core.management.base import BaseCommand, CommandError
+from django.core.management.base import BaseCommand
 
 
 class Command(BaseCommand):

tests/mail/test_sendtestemail.py

@@ -2,7 +2,6 @@ from __future__ import unicode_literals
 
 from django.core import mail
 from django.core.management import call_command
-from django.core.management.base import CommandError
 from django.test import SimpleTestCase