import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,-18))
w1=cq.Workplane('YZ',origin=(-21,0,0))
r=w0.workplane(offset=36/2).moveTo(24,0).cylinder(36,26).union(w1.sketch().segment((0,-9),(8,-9)).segment((8,-6)).segment((0,-6)).segment((0,-7)).close().assemble().finalize().extrude(-29))