refactor: Remove six.moves.filter import.

analytics/views.py

@@ -35,7 +35,6 @@ import pytz
 import re
 import time
 
-from six.moves import filter
 from typing import Any, Callable, Dict, List, Optional, Set, Text, \
     Tuple, Type, Union
 

tools/check-templates

@@ -6,8 +6,6 @@ import argparse
 import sys
 import logging
 
-from six.moves import filter
-
 # check for the venv
 from lib import sanity_check
 sanity_check.check_venv(__file__)

tools/html-grep

@@ -3,7 +3,6 @@ from lib.html_grep import grep
 import argparse
 import sys
 
-from six.moves import filter
 from typing import List
 
 # check for the venv

zerver/lib/actions.py

@@ -81,7 +81,6 @@ from django.utils.timezone import now as timezone_now
 
 from confirmation.models import Confirmation, create_confirmation_link
 from confirmation import settings as confirmation_settings
-from six.moves import filter
 from six import unichr
 
 from zerver.lib.create_user import random_api_key

zerver/lib/events.py

@@ -7,7 +7,6 @@ import ujson
 from django.utils.translation import ugettext as _
 from django.conf import settings
 from importlib import import_module
-from six.moves import filter
 from typing import (
     cast, Any, Callable, Dict, Iterable, List, Optional, Sequence, Set, Text, Tuple, Union
 )

zerver/tests/test_management_commands.py

@@ -4,7 +4,6 @@ import os
 import glob
 from datetime import timedelta
 from mock import MagicMock, patch
-from six.moves import filter
 from typing import List, Dict, Any, Optional
 
 from django.conf import settings