typing: Remove now-unnecessary conditional import.

As a result of dropping support for trusty, we can remove our old
pattern of putting `if False` before importing the typing module,
which was essential for Python 3.4 support, but not required and maybe
harmful on newer versions.

cron_file_helper
check_rabbitmq_consumers
hash_reqs
check_zephyr_mirror
check_personal_zephyr_mirrors
check_cron_file
zulip_tools
check_postgres_replication_lag
api_test_helpers
purge-old-deployments
setup_venv
node_cache
clean_venv_cache
clean_node_cache
clean_emoji_cache
pg_backup_and_purge
restore-backup
generate_secrets
zulip-ec2-configure-interfaces
diagnose
check_user_zephyr_mirror_liveness

scripts/lib/clean_emoji_cache.py

@@ -3,9 +3,7 @@ import argparse
 import os
 import sys
 
-if False:
-    # See https://zulip.readthedocs.io/en/latest/testing/mypy.html#mypy-in-production-scripts
-    from typing import Set
+from typing import Set
 
 ZULIP_PATH = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 sys.path.append(ZULIP_PATH)

scripts/lib/clean_node_cache.py

@@ -4,9 +4,7 @@ import os
 import subprocess
 import sys
 
-if False:
-    # See https://zulip.readthedocs.io/en/latest/testing/mypy.html#mypy-in-production-scripts
-    from typing import Set
+from typing import Set
 
 ZULIP_PATH = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 sys.path.append(ZULIP_PATH)

scripts/lib/clean_venv_cache.py

@@ -3,9 +3,7 @@ import argparse
 import os
 import sys
 
-if False:
-    # See https://zulip.readthedocs.io/en/latest/testing/mypy.html#mypy-in-production-scripts
-    from typing import Set
+from typing import Set
 
 ZULIP_PATH = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 sys.path.append(ZULIP_PATH)

scripts/lib/hash_reqs.py

@@ -3,10 +3,7 @@ import os
 import sys
 import argparse
 import hashlib
-
-if False:
-    # See https://zulip.readthedocs.io/en/latest/testing/mypy.html#mypy-in-production-scripts
-    from typing import Iterable, List, MutableSet
+from typing import Iterable, List, MutableSet
 
 def expand_reqs_helper(fpath, visited):
     # type: (str, MutableSet[str]) -> List[str]

scripts/lib/node_cache.py

@@ -3,10 +3,7 @@ import os
 import hashlib
 import json
 
-if False:
-    # See https://zulip.readthedocs.io/en/latest/testing/mypy.html#mypy-in-production-scripts
-    from typing import Optional, List, IO, Any
-
+from typing import Optional, List, IO, Any
 from scripts.lib.zulip_tools import subprocess_text_output, run
 
 ZULIP_PATH = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

scripts/lib/setup_venv.py

@@ -7,6 +7,8 @@ import sys
 from scripts.lib.zulip_tools import run, run_as_root, ENDC, WARNING
 from scripts.lib.hash_reqs import expand_reqs
 
+from typing import List, Optional, Tuple, Set
+
 ZULIP_PATH = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 VENV_CACHE_PATH = "/srv/zulip-venv-cache"
 
@@ -14,10 +16,6 @@ if 'TRAVIS' in os.environ:
     # In Travis CI, we don't have root access
     VENV_CACHE_PATH = "/home/travis/zulip-venv-cache"
 
-if False:
-    # See https://zulip.readthedocs.io/en/latest/testing/mypy.html#mypy-in-production-scripts
-    from typing import List, Optional, Tuple, Set
-
 VENV_DEPENDENCIES = [
     "build-essential",
     "libffi-dev",

scripts/lib/zulip_tools.py

@@ -16,9 +16,7 @@ import json
 import uuid
 import configparser
 
-if False:
-    # See https://zulip.readthedocs.io/en/latest/testing/mypy.html#mypy-in-production-scripts
-    from typing import Sequence, Set, Any, Dict, List
+from typing import Sequence, Set, Any, Dict, List
 
 DEPLOYMENTS_DIR = "/home/zulip/deployments"
 LOCK_DIR = os.path.join(DEPLOYMENTS_DIR, "lock")