As previously announced, IDA 7.4 comes with Python 3 support out of the box. Since the vast majority of existing scripts and plugins were written for Python 2, it is still supported and remains the default. However, you don’t have to be stuck with one version: it is possible to switch between Python 2 and Python 3 and even between different versions of Python 3 without reinstalling IDA.

We have prepared a porting guide for switching to Python 3 for anyone who elects to go with Python 3, and might have to do some adjustments to their scripts.