mypy: Annotate helloworld bot.

zulip_bots/zulip_bots/bots/helloworld/helloworld.py

@@ -1,8 +1,9 @@
 # See readme.md for instructions on running this code.
 
+from typing import Any
 
 class HelloWorldHandler(object):
-    def usage(self):
+    def usage(self) -> str:
         return '''
         This is a boilerplate bot that responds to a user query with
         "beep boop", which is robot for "Hello World".
@@ -11,8 +12,8 @@ class HelloWorldHandler(object):
         sophisticated, bots.
         '''
 
-    def handle_message(self, message, bot_handler):
-        content = 'beep boop'
+    def handle_message(self, message: Any, bot_handler: Any) -> None:
+        content = 'beep boop'  # type: str
         bot_handler.send_reply(message, content)
 
 handler_class = HelloWorldHandler

zulip_bots/zulip_bots/bots/helloworld/test_helloworld.py

@@ -3,9 +3,9 @@
 from zulip_bots.test_lib import StubBotTestCase
 
 class TestHelpBot(StubBotTestCase):
-    bot_name = "helloworld"
+    bot_name = "helloworld"  # type: str
 
-    def test_bot(self):
+    def test_bot(self) -> None:
         dialog = [
             ('', 'beep boop'),
             ('help', 'beep boop'),