fix some mypy lint

hotdog/bot.py

@@ -46,7 +46,7 @@ class Bot:
         self.message_handlers.append(callback)
 
     def on_command(self, command: Union[str, Container[str]], callback: MessageHandler):
-        commands = command = {command} if type(command) is str else command
+        commands = {command} if type(command) is str else command
 
         async def guard(message):
             if message.command not in commands:
@@ -161,7 +161,7 @@ class Bot:
         for h, t in tasks.items():
             assert t.done()
             try:
-                err = t.exception()
+                err = t.exception()  # type: ignore
             except asyncio.CancelledError:
                 log.error("Message handler took too long to finished: %s", h)
             if err is not None:

hotdog/functions.py

@@ -3,7 +3,7 @@ import logging
 import unicodedata
 from collections import defaultdict
 from contextlib import contextmanager
-from dataclasses import dataclass, fields
+from dataclasses import fields
 from datetime import datetime, timedelta, timezone
 from html import escape as html_escape
 from html.parser import HTMLParser
@@ -311,7 +311,7 @@ class ElementParser(HTMLParser):
                 break
 
 
-def escape_all(dc: dataclass, escape: Callable[[str], str] = html_escape) -> None:
+def escape_all(dc, escape: Callable[[str], str] = html_escape) -> None:
     """Patch a dataclass to escape all strings."""
     for f in fields(dc):
         if f.type is str: