import cadquery as cq
w0=cq.Workplane('ZX',origin=(0,-1,0))
r=w0.sketch().segment((-3,-43),(17,-43)).segment((17,-3)).arc((8,20),(-2,-2)).segment((-3,-2)).close().assemble().reset().face(w0.sketch().segment((0,-2),(16,-2)).arc((8,19),(0,-2)).assemble(),mode='s').finalize().extrude(-2).union(w0.sketch().push([(-18,-40)]).rect(14,20).push([(10,35)]).circle(15).finalize().extrude(4))