import cadquery as cq
w0=cq.Workplane('ZX',origin=(0,-12,0))
w1=cq.Workplane('YZ',origin=(18,0,0))
r=w0.workplane(offset=39/2).moveTo(-38,10).cylinder(39,12).union(w1.sketch().segment((-20,13),(-20,15)).segment((-15,15)).segment((-15,9)).arc((10,44),(-20,13)).assemble().push([(-6,16)]).rect(10,18,mode='s').finalize().extrude(-40))