code: def update_n_sides(value):
      """Callback to set the number of sides."""
      res = round(value)
      poly_source.SetNumberOfSides(res)
  
imports: import vtk
  import pyvista
  from pyvista import examples
label_desc: Use image node_id 2 for calling a global function with example usage: update_n_sides(value) without return types