Lirc in virtual environment

I just got started with the rpi and HA using the all in one installer. I’m following the instructions on the LIRC page.

I’m stuck at this point.
“As the user that runs hass”

How do I change user to hass? I went searching around and found this command. sudo su -s /bin/bash hass

I think that’s right, is it?

Then when I do the following commands
(hass) $ git clone
(hass) $ cd python-lirc
(hass) $ make py3

On “make py3” I get the following error
“hass@raspberrypi:~/python-lirc$ make py3
cython -3 -a lirc/lirc.pyx
make: cython: Command not found
Makefile:2: recipe for target ‘py3’ failed
make: *** [py3] Error 127

any help would be greatly appreciated thanks