import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,24))
r=w0.workplane(offset=-48/2).moveTo(-36,-24.5).box(28,5,48).union(w0.sketch().push([(-5,-35)]).rect(14,18).push([(27,21)]).circle(23).circle(7,mode='s').finalize().extrude(-45))