import cadquery as cq
w0=cq.Workplane('YZ',origin=(25,0,0))
r=w0.sketch().arc((-24,-49),(-18,-50),(-12,-49)).close().assemble().push([(30,46.5)]).rect(22,7).finalize().extrude(-51).union(w0.workplane(offset=-22/2).moveTo(-24,17.5).box(34,15,22))