it probably is as others have mentioned, the snake realized it made a mistake and let go.
i've had it happen with diferent species over the years..
then you have some snakes who will not let go (usually a water spray bottle works) and having a little vinigar really works because of the taste and smell . you even have snakes who will accidently bite and eat themselves !!!!
but I have read many reports from experts citing that the reticulated python is one of the most intelligent of all snakes.. they are one of the only snakes who will sit there and watch you and follow you .. some real interesting reads out there regarding retics.
it's also one of the reasons why hook traing them is easy.
my girl will almost always come out of her hide and watch me clean cages then if/when it's her turn, she always lifts her head up to smell me and goes back in her hide while i clean.. pretty cool.
only other snakes that i have who act odd are my emeralds, most of them when i got them, were nervous because of bad conditions they were in with the previous owner.
after a while in perfetc conditions they all calmed down and now they don't come at me when i open the cage, instead they will tilt their head to have one eye looking at me..
as if saying, go ahead do your thing i'm watching you hehehehe others won't even bother moving at all..
now they are not going to have feelings for you
but they are known to learn and get to know their owner.
there's still is a slight chance that it did look at you and realized who/what it grabed..
most is instinct but they do learn and are smarter than it's believed..
I will hunt down some of the articles just for fun...