import cadquery as cq
w0=cq.Workplane('YZ',origin=(50,0,0))
w1=cq.Workplane('ZX',origin=(0,25,0))
r=w0.sketch().segment((-25,-36),(-3,-42)).segment((1,-28)).close().assemble().finalize().extrude(-26).union(w1.sketch().segment((13,-50),(42,-50)).segment((42,-46)).arc((27,-48),(13,-46)).close().assemble().finalize().extrude(-48))