import cadquery as cq
w0=cq.Workplane('YZ',origin=(-78,0,0))
r=w0.workplane(offset=90/2).moveTo(18,29).box(164,124,90).union(w0.sketch().segment((-100,-91),(-97,-91)).arc((-98,-89),(-100,-87)).close().assemble().finalize().extrude(157))