Refers to the large constrictor snake. The Japanese term 錦蛇 (にしきへび) is also used, but パイソン is common in loanword contexts.
See also: ニシキヘビ (にしきへび)
I saw a large python at the zoo.
Refers to the Python programming language. In computing contexts, it is almost always written in katakana as パイソン.
He is writing a machine learning program in Python.