Hi there,
A brand new Matomo user here 
We set up Matomo on various of our sites and everthing seems to work just fine.
According to new EU laws we need to inform our vistitors about the data we gather, including cookies.
Now Matomo is using 2 cookies in our case:
_pk_ses
_pk_id
What functions do these cookies have and what’s their duration?
Can someone help us out? Thanks!