class_docstr: Class to support multiple render passes for a renderer.
  
  Notes
  -----
  Passes are organized here as "primary" (vtkOpenGLRenderPass) that act
  within the renderer and "post-processing" (vtkImageProcessingPass) passes,
  which act on the image generated from the renderer.
  
  The primary passes are added as part of a vtk.vtkRenderPassCollection or
  are "stacked", while the post-processing passes are added as a final pass
  to the rendered image.
  
  Parameters
  ----------
  renderer : vtk.vtkRenderer
      Renderer to initialize render passes for.
docstr: Enable the EDL pass.
  
  Returns
  -------
  vtk.vtkEDLShading
      The enabled EDL pass.
docstr_tok: ["Enable","the","EDL","pass",".","Returns","--","--","--","-","vtk.vtkEDLShading","The","enabled","EDL","pass","."]
code: def enable_edl_pass(self):
      """Enable the EDL pass.
  
      Returns
      -------
      vtk.vtkEDLShading
          The enabled EDL pass.
  
      """
      if self._edl_pass is not None:
          return
      self._edl_pass = _vtk.vtkEDLShading()
      self._add_pass(self._edl_pass)
      return self._edl_pass
  
imports: import weakref
  from .None import _vtk
label_desc: Use image node_id 8 for calling the RenderPasses obj's underlying member method code with example usage: obj.enable_edl_pass() and returns: self