def demo_FittedSplines_add(sketch: adsk.fusion.Sketch):
# Create an object collection for the points.
points = adsk.core.ObjectCollection.create()
# Define the points the spline with fit through.
points.add(adsk.core.Point3D.create(0, 0, 0))
points.add(adsk.core.Point3D.create(5, 1, 0))
points.add(adsk.core.Point3D.create(6, 4, 3))
points.add(adsk.core.Point3D.create(7, 6, 6))
points.add(adsk.core.Point3D.create(2, 3, 0))
points.add(adsk.core.Point3D.create(0, 1, 0))
# Create the spline
splines = sketch.sketchCurves.sketchFittedSplines
spline = splines.add(points)