Ignores a specific channel from being processed.

        If no channel is specified, the current channel is ignored.
        If a channel is ignored then the bot does not process commands in that
        channel until it is unignored.

async def channel_cmd(self, ctx, *, channel : discord.Channel = None):
        """Ignores a specific channel from being processed.

        If no channel is specified, the current channel is ignored.
        If a channel is ignored then the bot does not process commands in that
        channel until it is unignored.
        """

        if channel is None:
            channel = ctx.message.channel

        ignored = self.config.get('ignored', [])
        if channel.id in ignored:
            await self.bot.responses.failure(message='That channel is already ignored.')
            return

        ignored.append(channel.id)
        await self.config.put('ignored', ignored)
        await self.bot.responses.success(message='Channel <#{}> will be ignored.'.format(channel.id))