import cadquery as cq
w0=cq.Workplane('YZ',origin=(31,0,0))
r=w0.sketch().segment((-50,1),(-10,1)).segment((-10,-21)).segment((10,-21)).segment((10,1)).segment((50,1)).segment((50,6)).segment((10,6)).segment((10,28)).segment((-10,28)).segment((-10,6)).segment((-50,6)).close().assemble().reset().face(w0.sketch().arc((-7,1),(0,-4),(7,1)).segment((3,1)).arc((4,3),(3,6)).segment((7,6)).arc((0,11),(-7,6)).segment((-3,6)).arc((-4,3),(-3,1)).close().assemble(),mode='s').push([(8,-27)]).circle(1).finalize().extrude(-63)