import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,50))
r=w0.sketch().segment((-32,8),(-28,8)).arc((-8,-4),(12,8)).segment((15,8)).segment((15,31)).segment((12,31)).arc((-8,42),(-28,31)).segment((-32,31)).close().assemble().finalize().extrude(-100).union(w0.workplane(offset=-53/2).moveTo(29,-39).cylinder(53,3))