The site-packages folder exists for python2 but not python3

As the root user I see:

root@5d6f29f1d4e9:/usr/local/lib/python2.7# ls -a
.  ..  dist-packages  site-packages
root@5d6f29f1d4e9:/usr/local/lib/python3.6# ls -a
.  ..  dist-packages

and when I run this:

find / -type d -name 'site-packages'

the only result is:

/usr/local/lib/python2.7/site-packages

does anyone know why I wouldn't see site-packages in 3.6?

I installed python3 with:

 apt install -y build-essential libssl-dev libffi-dev python3-dev
 apt install -y python3-pip

and then installed a bunch of python package using:

 pip3 install gunicorn
 pip3 install wheel
 ...etc...

maybe I didn't install python3 well?

from The site-packages folder exists for python2 but not python3