New adopted male ball python hisses at only me...

Question
I have a juvenile male ball I purchased on june that is great we handle him every day which he is very spoiled no problems at all , I recently adopted a 10 yr old male ball which was very friendly as long as the previous owner had him and with everyone in the pet store , once I got him home I let him be for a few days , then I only let him out when he is active at night, when I put him back in his tank or when I close his tank top or go by his tank he hissed at me , and only me, he is in his original tank ( 55 gallon) has everything he needs heaters , artificialplants , log, the right bedding you name it. What do I do , he was extremely friendly  with eveyone , but I am not used to this? I have never been bitten by a snake , I actually this year got over my fear of them ...

Answer
They do that...  I have a big burmese I use in my classroom and even she will sometimes hiss at me.  Remember snakes have an IQ of say 7 so they simply aren't really intelligent enough to learn to like us.  Being held is probably a "new" experience each time it happens as they don't remember the last time.  Just be careful and don't reach into the tank like a giant bird coming to eat the snake.