Enables a command for this server.

        You must have Manage Server permissions or the
        Bot Admin role to use this command.

async def enable(self, ctx, *, command: str):
        """Enables a command for this server.

        You must have Manage Server permissions or the
        Bot Admin role to use this command.
        """
        command = command.lower()
        guild_id = ctx.message.server.id
        cmds = self.config.get('commands', {})
        entries = cmds.get(guild_id, [])

        try:
            entries.remove(command)
        except KeyError:
            await self.bot.responses.failure(message='The command does not exist or is not disabled.')
        else:
            cmds[guild_id] = entries
            await self.config.put('commands', cmds)
            await self.bot.responses.success(message='"%s" command enabled in this server.' % command)