import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,-4))
r=w0.sketch().push([(-39,-22.5)]).rect(22,55).reset().face(w0.sketch().segment((-19,12),(-4,12)).arc((7,9),(18,12)).segment((31,12)).segment((31,36)).segment((26,36)).arc((7,50),(-12,36)).segment((-19,36)).close().assemble()).finalize().extrude(-46).union(w0.sketch().segment((-12,-30),(31,-30)).segment((31,-9)).segment((22,-9)).segment((22,-15)).segment((9,-15)).segment((9,-9)).segment((-12,-9)).close().assemble().finalize().extrude(-6)).union(w0.workplane(offset=54/2).moveTo(44,-37.5).box(12,23,54))