python or python3 for ros melodic?

[felixf4xu]

Hi,

I'm reading the autoware.ai document while I install autoware.ai 1.13 from source.

it says (https://github.com/autowarefoundation/autoware_ai_documentation/wiki/Source-Build#system-dependencies-for-ubuntu-1804--melodic):

$ sudo apt install -y python3-pip python3-colcon-common-extensions python3-setuptools python3-vcstool
$ pip3 install -U setuptools

I'm curious that I heard ros melodic only supports python 2 (not python 3), if autoware.ai runs on melodic, what's the point to install python3 for autoware.ai?