added command to retrieve username from id

README.md

@@ -37,6 +37,7 @@ so if you did !ignoreme, I will still know that you don't want to be complemente
 twitch username/user id will still be stored in my database. If you don't want this, then also do !unignore me - 
 this will remove any reference of you from my database
 - !userid - returns the twitch user's ID from their username; if no name specified, returns ID of caller
+- !username - returns the twitch user's name from their ID
 
 - !ignoreme - I will stop complementing you
 - !unignoreme - undo !ignoreme

src/complements_bot/bot.py

@@ -598,6 +598,22 @@ async def userid(self, ctx: commands.Context) -> None:
                 userid
         )
 
+    @commands.command()
+    async def username(self, ctx: commands.Context) -> None:
+        """
+        Get the twitch user's ID from their username
+        """
+
+        username: str = str(await self.id_to_name(self.isolate_args(ctx.message.content)))
+
+        await ComplementsBot.cmd_body(
+                ctx,
+                self.is_in_bot_channel,
+                None,
+                None,
+                username
+        )
+
     @commands.command()
     async def unignoreme(self, ctx: commands.Context) -> None:
         """