code: def _smoothing(
      self,
      smoothing_iterations: int,
      pass_band: float,
      feature_angle: int,
      contour: typing.Any,
  ) -> typing.Any:
      smoother = vtk.vtkWindowedSincPolyDataFilter()
      smoother.SetInputConnection(contour.GetOutputPort())
      smoother.SetNumberOfIterations(smoothing_iterations)
      smoother.BoundarySmoothingOff()
      smoother.FeatureEdgeSmoothingOff()
      smoother.SetFeatureAngle(feature_angle)
      smoother.SetPassBand(pass_band)
      smoother.NonManifoldSmoothingOn()
      smoother.NormalizeCoordinatesOn()
      smoother.Update()
      return smoother
  
file_path: PaddleSeg/EISeg/eiseg/widget/vtk.py
imports: import typing
  import numpy
  from qtpy.QtWidgets import QWidget, QVBoxLayout
label_desc: Use image node_id 6 for calling the VTKWidget obj's underlying member method code with example usage: obj._smoothing(smoothing_iterations, pass_band, feature_angle, contour) and returns: smoother