Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
This British production about a vampire cult led by a several-hundred-year old vampire named Sinistre, the Devil of Darkness, is one of those movies that's so bad it's not even good. But there is enough ridiculous snake nonsense to make it almost worth watching.
In the first snake scene, a scientist tells Paul, whose friends were killed by a vampire, that he's working with snake venom and its effect on animals. We see a Burmese Python in a glass tank. The scientist talks about The Evil Eye, referencing the vampire's ability to hypnotize his victims, and tells Paul that the snake hypnotizes his victim and makes it freeze, then the snake makes its strike. (The vampire's magic emblem even shows a bat with a snake.) This is all a silly snake myth. People actually once thought that snakes hypnotized their prey. And the python we see does not have any venom. (Nonetheless, in movies all snakes are venomous.)
Later we see the python escaping from its cage. Thunder crashes, the lights go out, and the scientist makes a terrified face. We hear from a police inspector that he was found with bite marks on his neck from the snake that escaped. Eventually the police determine that the snake's poison was already extracted by the scientist in his research, and that the bite marks were from a vampire.
At the end of the movie, just before they intend to kill a young woman as a midnight sacrifice in the basement, the vampire cult has a cocktail party in the vampire's living room, with lots of booze and a scantily-clad woman who dances with a Boa Constrictor.