import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,-1))
r=w0.workplane(offset=-29/2).moveTo(2,-27).cylinder(29,4).union(w0.sketch().push([(-20,-12)]).circle(30).push([(29,21)]).circle(21).push([(29.5,21)]).rect(39,4,mode='s').finalize().extrude(32))