I tried to make blacklist system in discord.py

class blackk(commands.CheckFailure): pass  def __global_check_once(ctx):     cursor.execute(f"SELECT ban_id FROM bany WHERE ban_id = {ctx.author.id}")     r = cursor.fetchone()     if r is not None:         raise blackk()     else:         return    @bot.event async def on_command_error(ctx, error):     if isinstance(error, blackk):         await ctx.send("blacklisted") 

I really need it. Someone know better way to do it (example please)