Definition: In this task, you are given a Reddit post as a text. Your task is to generate a title for this text. The title should start with "TIFU by", followed by a situation that caused humor. The title should contain 7-12 words, ideally.
Input: Text: a friend just reminded me about the most embarassing day of my existence (so far- for you, brightsided beings-), so i figured i will share it with you. 

it was 2012, i was in my second to last year of high school, my 40 classmates and i were travelling by bus on our 2-week long yearly trip. the road trip was terrible by itself. putting 40 impatient and energetic kids inside a bus with a malfunctioning ac for 14 hours is already a recipe for disaster. little did i know that i was about to make it worse...

i was sitting on the bottom part of the bus, right at the back (yes, i was one of the cool kids). like everyone in there, i was irritated by the seemingly endless drive, when i decided it would be a good idea to stretch out for a bit. i proceeded to rest my right arm on the fire extinguisher hanging next to me, and at that exact moment all hell broke loose. in a matter of seconds, the inside of the bus was covered by this thick grey gas. people coughing, people screaming...hell, even girls crying in all this confusion.

we were immediately ordered to get off the bus. i was blamed and scolded by the teachers who accused me of doing it on purpose. although some of my friends found it hilarious, most of my classmates were utterly annoyed by the lenghtening of the already long trip. i was not so cool anymore...

TIFU by resting my arm on a fire extinguisher