Support saving history.

tests/test_main.py

@@ -111,12 +111,8 @@ class TestFunctionality(TestBotBase):
     async def test_on_message_event3(self) -> None:
         async def acreate(*a, **kw):
             return {'choices': [{'message': {'content': '{ "test": 3 ]'}}]}
-
-        def logging_warning(msg):
-            raise RuntimeError(msg)
         message = self.create_message("Hello there! How are you?")
-        with patch.object(openai.ChatCompletion, 'acreate', new=acreate), \
-             patch.object(logging, 'warning', logging_warning):
+        with patch.object(openai.ChatCompletion, 'acreate', new=acreate):
             await self.bot.on_message(message)
         self.bot.staff_channel.send.assert_called_once_with("ERROR: I could not parse this answer: '{ \"test\": 3 ]'", suppress_embeds=True)