As an owner of a snake (not python just a corn snake) the only possible explanation i can see as the snake didn't eat is that it was a tragic accident. Our corn snake is only 3.5ft long but when we hold him to move up our arms he will wrap his body around our wrists and it can become quite tight.
this python was 14ft long it could well of just wrapped itself round the boys as it moved along, cold snakes will also curl up on/around warm places as to restore their energy.
either this or there is something fishy about the story, snakes will not waste there energy on constricting unless they are going to eat it, if a snake feels threatened it will bite or just slither away