python: Sort imports with isort.

Fixes #2665.

Regenerated by tabbott with `lint --fix` after a rebase and change in
parameters.

Note from tabbott: In a few cases, this converts technical debt in the
form of unsorted imports into different technical debt in the form of
our largest files having very long, ugly import sequences at the
start.  I expect this change will increase pressure for us to split
those files, which isn't a bad thing.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

analytics/views.py

@@ -6,54 +6,75 @@ import urllib
 from collections import defaultdict
 from datetime import datetime, timedelta, timezone
 from decimal import Decimal
-
-from typing import Any, Callable, Dict, List, \
-    Optional, Set, Tuple, Type, Union
+from typing import Any, Callable, Dict, List, Optional, Set, Tuple, Type, Union
 
 import pytz
 from django.conf import settings
-from django.urls import reverse
+from django.core.exceptions import ValidationError
+from django.core.validators import URLValidator
 from django.db import connection
 from django.db.models.query import QuerySet
 from django.http import HttpRequest, HttpResponse, HttpResponseNotFound
 from django.shortcuts import render
 from django.template import loader
+from django.urls import reverse
+from django.utils.timesince import timesince
 from django.utils.timezone import now as timezone_now
 from django.utils.translation import ugettext as _
-from django.utils.timesince import timesince
-from django.core.validators import URLValidator
-from django.core.exceptions import ValidationError
 from jinja2 import Markup as mark_safe
-from psycopg2.sql import Composable, Literal, SQL
+from psycopg2.sql import SQL, Composable, Literal
 
 from analytics.lib.counts import COUNT_STATS, CountStat
 from analytics.lib.time_utils import time_range
-from analytics.models import BaseCount, InstallationCount, \
-    RealmCount, StreamCount, UserCount, last_successful_fill, installation_epoch
-from confirmation.models import Confirmation, confirmation_url, _properties
-from zerver.decorator import require_server_admin, require_server_admin_api, \
-    to_utc_datetime, zulip_login_required, require_non_guest_user
+from analytics.models import (
+    BaseCount,
+    InstallationCount,
+    RealmCount,
+    StreamCount,
+    UserCount,
+    installation_epoch,
+    last_successful_fill,
+)
+from confirmation.models import Confirmation, _properties, confirmation_url
+from confirmation.settings import STATUS_ACTIVE
+from zerver.decorator import (
+    require_non_guest_user,
+    require_server_admin,
+    require_server_admin_api,
+    to_utc_datetime,
+    zulip_login_required,
+)
+from zerver.lib.actions import (
+    do_change_plan_type,
+    do_deactivate_realm,
+    do_scrub_realm,
+    do_send_realm_reactivation_email,
+)
 from zerver.lib.exceptions import JsonableError
+from zerver.lib.realm_icon import realm_icon_url
 from zerver.lib.request import REQ, has_request_variables
 from zerver.lib.response import json_success
-from zerver.lib.timestamp import convert_to_UTC, timestamp_to_datetime
-from zerver.lib.realm_icon import realm_icon_url
-from zerver.views.invite import get_invitee_emails_set
 from zerver.lib.subdomains import get_subdomain_from_hostname
-from zerver.lib.actions import do_change_plan_type, do_deactivate_realm, \
-    do_send_realm_reactivation_email, do_scrub_realm
+from zerver.lib.timestamp import convert_to_UTC, timestamp_to_datetime
 from zerver.lib.validator import to_non_negative_int
-from confirmation.settings import STATUS_ACTIVE
+from zerver.views.invite import get_invitee_emails_set
 
 if settings.BILLING_ENABLED:
     from corporate.lib.stripe import attach_discount_to_realm, get_discount_for_realm
 
-from zerver.models import Client, get_realm, Realm, UserActivity, UserActivityInterval, \
-    UserProfile, PreregistrationUser, MultiuseInvite
+from zerver.models import (
+    Client,
+    MultiuseInvite,
+    PreregistrationUser,
+    Realm,
+    UserActivity,
+    UserActivityInterval,
+    UserProfile,
+    get_realm,
+)
 
 if settings.ZILENCER_ENABLED:
-    from zilencer.models import RemoteInstallationCount, RemoteRealmCount, \
-        RemoteZulipServer
+    from zilencer.models import RemoteInstallationCount, RemoteRealmCount, RemoteZulipServer
 else:
     from unittest.mock import Mock
     RemoteInstallationCount = Mock()  # type: ignore[misc] # https://github.com/JukkaL/mypy/issues/1188