I finally set up my first auto-email script... and it blew up in my face

I was so excited about my new Python script that handled daily updates... but I forgot to check the recipient list. It ended up sending a hundred copies to every single person in the company, including the top boss. My team lead called me laughing, saying his inbox was flooded before lunch. Now I always double-check my code for silly mistakes like that... learning the hard way, I guess.