I don not believe a python can quickly release its prey quickly in order to strike.
A snake unlatched its jaw to swallow prey.
To strike it would have to release the prey animal and rematch the jaw.
Also a snakes teeth are hook shaped pointed to the back of the head to make it more difficult for prey to escape and to move the prey toward the throat. This would also make it difficult to release the dog.
Thanks for the information. I knew about the teeth being slanted backwards but not about its unlatching its jaw.