def demo_holeFeatures_add_countersink(rootComp: adsk.fusion.Design.rootComponent):
# Have the face and edges selected.
face: adsk.fusion.BRepFace = _ui.selectEntity('Select a face', 'Faces').entity
circleEdge: adsk.fusion.BRepEdge = _ui.selectEntity('Select circular edge', 'CircularEdges').entity
# Define the needed inputs.
holeDiam = adsk.core.ValueInput.createByString('20 mm')
holeDepth = adsk.core.ValueInput.createByReal(5)
countersinkDiam = adsk.core.ValueInput.createByString('35 mm')
countersinkAngle = adsk.core.ValueInput.createByString('120 deg')
holeFeatures: adsk.fusion.HoleFeatures = rootComp.features.holeFeatures
input = holeFeatures.createCountersinkInput(holeDiam, countersinkDiam, countersinkAngle)
input.setDistanceExtent(holeDepth)
input.setPositionAtCenter(face, circleEdge)
holeFeature = holeFeatures.add(input)