import cadquery as cq
w0=cq.Workplane('XY',origin=(0,0,-50))
r=w0.sketch().segment((-29,-21),(-7,-21)).segment((-7,-16)).segment((29,-16)).segment((29,15)).segment((2,15)).segment((2,21)).segment((-2,21)).segment((-2,15)).segment((-29,15)).close().assemble().finalize().extrude(100)