i'm sorry but you're way off base here. where do i begin. first off kangaroos aren't marsupials, they're mammals. a marsupial is a small mammal like a guinea pig, is there anything about the kangaroo that looks small to you? secondly nothing is immune to snake poisons except for reptiles. this is common knowledge
under what circumstances does this matchup take place? i can tell you for a fact that the kangaroo could only compete in warm summer weather, kangaroos are warm-blooded and would have no chance is sub-temperate conditions. python is cold-blooded meaning it can never get cold (doesn't need heat), so anything below 90F is a write-off, easy W. next question, is this fight happening during the day or at night? kangaroos have mammal eyes, mammal eyes are simply useless without light. the python on the other hand has reptile eyes, reptile eyes are incredible at night vision because they can glow (produce their own light)
if you're going to sit there and tell me a blind shivering kangaroo has any chance against a game python then i'm not even going to bother continuing this conversation