import cadquery as cq
w0=cq.Workplane('ZX',origin=(0,-11,0))
w1=cq.Workplane('YZ',origin=(-17,0,0))
r=w0.workplane(offset=18/2).moveTo(26.5,0).box(43,38,18).union(w0.sketch().segment((-50,-36),(0,-36)).arc((44,21),(-26,2)).segment((-50,2)).close().assemble().push([(-18.5,-17)]).rect(51,10,mode='s').reset().face(w0.sketch().segment((7,2),(12,2)).segment((12,-7)).segment((17,-7)).segment((17,7)).segment((7,7)).close().assemble(),mode='s').finalize().extrude(57)).union(w1.workplane(offset=8/2).moveTo(-26,12).box(40,22,8))