Exactly. We picked it for the reasons you mentioned, and I still think it's a good choice.

That said, some of our heavier logic is in a lower-level language. We had some Fortran code until recently (rewrote in Python and just ate the perf cost to lower barrier to other devs fixing stuff), and we're introducing some C++ code in the next month or two. But the bulk of our code is in Python, because that's what glues everything together, and the code is fast enough for our needs.