import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,-22))
w1=cq.Workplane('XY',origin=(0,0,-16))
r=w0.sketch().segment((-44,-36),(-24,-36)).segment((-21,-3)).segment((44,-9)).segment((44,36)).segment((-44,36)).close().assemble().finalize().extrude(48).union(w1.sketch().segment((-33,-50),(33,-50)).segment((33,-35)).arc((48,0),(33,35)).segment((33,50)).segment((-33,50)).segment((-33,35)).arc((-48,0),(-33,-35)).close().assemble().finalize().extrude(-10))