# Buggy code
async def dj(self, ctx: commands.Context):
    """Toggle DJ mode.

    DJ mode allows users with the DJ role to use audio commands.
    """
    dj_role = ctx.guild.get_role(await self.config.guild(ctx.guild).dj_role())
    if dj_role is None:
        await self._embed_msg(
            ctx,
            _("Please set a role to use with DJ mode. Enter the role name or ID now."),
        )

        try:
            pred = MessagePredicate.valid_role(ctx)
            await ctx.bot.wait_for("message", timeout=15.0, check=pred)
            await ctx.invoke(self.role, pred.result)
        except asyncio.TimeoutError:
            return await self._embed_msg(ctx, _("Response timed out, try again later."))

    dj_enabled = await self.config.guild(ctx.guild).dj_enabled()
    await self.config.guild(ctx.guild).dj_enabled.set(not dj_enabled)
    await self._embed_msg(
        ctx,
        _("DJ role: {true_or_false}.").format(
            true_or_false=_("Enabled") if not dj_enabled else _("Disabled")
        ),
    )


# Traceback (RuntimeError)
Traceback (most recent call last):
File "/home/martinebots/martinebotsvenv/lib/python3.7/site-packages/discord/ext/commands/core.py", line 79, in wrapped
ret = await coro(*args, **kwargs)
File "/home/martinebots/martinebotscogs/cogs_modified/audio/audio.py", line 3183, in play
await self._enqueue_tracks(ctx, query)
File "/home/martinebots/martinebotscogs/cogs_modified/audio/audio.py", line 3885, in _enqueue_tracks
result, called_api = await self.music_cache.lavalink_query(ctx, player, query)
File "/home/martinebots/martinebotscogs/cogs_modified/audio/apis.py", line 911, in lavalink_query
results = await player.load_tracks(query)
File "/home/martinebots/martinebotsvenv/lib/python3.7/site-packages/lavalink/rest_api.py", line 300, in load_tracks
self.__check_node_ready()
File "/home/martinebots/martinebotsvenv/lib/python3.7/site-packages/lavalink/rest_api.py", line 268, in __check_node_ready
raise RuntimeError("Cannot execute REST request when node not ready.")
RuntimeError: Cannot execute REST request when node not ready.

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
File "/home/martinebots/martinebotsvenv/lib/python3.7/site-packages/discord/ext/commands/bot.py", line 863, in invoke
await ctx.command.invoke(ctx)
File "/home/martinebots/martinebotsvenv/lib/python3.7/site-packages/discord/ext/commands/core.py", line 728, in invoke
await injected(*ctx.args, **ctx.kwargs)
File "/home/martinebots/martinebotsvenv/lib/python3.7/site-packages/discord/ext/commands/core.py", line 88, in wrapped
raise CommandInvokeError(exc) from exc
discord.ext.commands.errors.CommandInvokeError: Command raised an exception: RuntimeError: Cannot execute REST request when node not ready.```

# Fixed code
async def dj(self, ctx: commands.Context):
    """Toggle DJ mode.

    DJ mode allows users with the DJ role to use audio commands.
    """
    dj_role = self._dj_role_cache.setdefault(
        ctx.guild.id, await self.config.guild(ctx.guild).dj_role()
    )
    dj_role = ctx.guild.get_role(dj_role)
    if dj_role is None:
        await self._embed_msg(
            ctx,
            title=_("Missing DJ Role"),
            description=_(
                "Please set a role to use with DJ mode. Enter the role name or ID now."
            ),
        )

        try:
            pred = MessagePredicate.valid_role(ctx)
            await ctx.bot.wait_for("message", timeout=15.0, check=pred)
            await ctx.invoke(self.role, role_name=pred.result)
        except asyncio.TimeoutError:
            return await self._embed_msg(
                ctx, title=_("Response timed out, try again later.")
            )
    dj_enabled = self._dj_status_cache.setdefault(
        ctx.guild.id, await self.config.guild(ctx.guild).dj_enabled()
    )
    await self.config.guild(ctx.guild).dj_enabled.set(not dj_enabled)
    self._dj_status_cache[ctx.guild.id] = not dj_enabled
    await self._embed_msg(
        ctx,
        title=_("Setting Changed"),
        description=_("DJ role: {true_or_false}.").format(
            true_or_false=_("Enabled") if not dj_enabled else _("Disabled")
        ),
    )