This is a part of my script where I insert the expression for each data set by hand. Of course there must be a nicer way to do this with loops etc.
The deprojected source expression is set by dep.set_source() for all data sets as explained in the Deproject documentation. Here I used just a standard XSPEC mekal model. Note that there are 2 annuli and each of them has 2 data sets. I add the same power law model component (p1 and p2) to each annulus.
get_model() allows you to inspect the full model expression.