Life is so amazing! This is a boa constrictor still in its amniotic sac that has just been born. Little guy hasn’t even had its first breath yet. So amazing to witness!
It might be strange to see a snake in a sack, rather than a soft-shell egg, like we are used to seeing them. But according to a page on Wikipedia, both reptiles (this includes snakes) and mammals are members of the clade “Amniotes”, meaning that these animals possess amniotic sacs. They may also further protect the fetus with a shell, but this is not necessarily the case for all amniotes and many species have gained and then lost shells as they evolved.
Chickens also have amniotic sacs in their eggs. There is an incredibly thin membrane between the shell and the egg white, which is technically the amniotic sac.
Despite the ominous part of their name, boa constrictors are actually quite frequently kept as domestic pets. The give birth to live young, where the mother bite through the sac to release the young. Boas are among the 30% of snakes that do give birth to their young, as opposed to pythons, which are classified as being ovoviviparous, meaning that their eggs emerge inside of the body.
Boa mothers carry their young for between 100 and 150 days. Boa litters typically account about 25 baby boa constrictors, but can be as low as 10 snakes to an incredible count of 64.