Python is used as a kind of 'visual basic' language in a lot of banks especially in front-of-house trading software, e.g murex or frontarena. Migrations between major versions of these can take years, costs 100s of millions and involve thousands of devs. Mistakes can be _expensive_.

It is kind of 'insane' but also, meh..

There's more dragons out there than we've been led to believe :}