import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,40))
r=w0.sketch().arc((9,-13),(23,18),(9,50)).close().assemble().finalize().extrude(-80).union(w0.workplane(offset=-38/2).moveTo(20,-44.5).box(18,11,38)).union(w0.workplane(offset=-14/2).moveTo(-19,18.5).box(20,59,14))