def demo_Arcs_addFillet(sketch: adsk.fusion.Sketch):
# Create two connected lines
lines = sketch.sketchCurves.sketchLines
startPoint = adsk.core.Point3D.create(0, 0, 0)
endPoint = adsk.core.Point3D.create(3, 1, 0)
line1 = lines.addByTwoPoints(startPoint, endPoint)
line2 = lines.addByTwoPoints(line1.endSketchPoint, adsk.core.Point3D.create(1, 4, 0))
# Create arc by adding fillet between the two lines
arcs = sketch.sketchCurves.sketchArcs
arc = arcs.addFillet(line1, line1.endSketchPoint.geometry, line2, line2.startSketchPoint.geometry, 1)