code: def add_impact_layers_to_canvas(impact_function, group=None, iface=None):
      
      layers = impact_function.outputs
      name = impact_function.name
  
      if group:
          group_analysis = group
      else:
          # noinspection PyArgumentList
          root = QgsProject.instance().layerTreeRoot()
          group_analysis = root.insertGroup(0, name)
          group_analysis.setItemVisibilityChecked(True)
  
      group_analysis.setExpanded(group is None)
  
      for layer in layers:
          # noinspection PyArgumentList
          QgsProject.instance().addMapLayer(layer, False)
          layer_node = group_analysis.addLayer(layer)
  
          # set layer title if any
          try:
              title = layer.keywords['title']
              if qgis_version() >= 21800:
                  layer.setName(title)
              else:
                  layer.setLayerName(title)
          except KeyError:
              pass
  
          visible_layers = [impact_function.impact.id()]
          print_atlas = setting('print_atlas_report', False, bool)
          if print_atlas:
              visible_layers.append(impact_function.aggregation_summary.id())
          # Let's enable only the more detailed layer. See #2925
          if layer.id() in visible_layers:
              layer_node.setItemVisibilityChecked(True)
          else:
              layer_node.setItemVisibilityChecked(False)
  
          # we need to set analysis_impacted as an active layer because we need
          # to get all qgis variables that we need from this layer for
          # infographic.
          if iface:
              iface.setActiveLayer(impact_function.analysis_impacted)
docs: Helper method to add impact layer to QGIS from impact function.
  
      :param impact_function: The impact function used.
      :type impact_function: ImpactFunction
  
      :param group: An existing group as a parent, optional.
      :type group: QgsLayerTreeGroup
  
      :param iface: QGIS QgisAppInterface instance.
      :type iface: QgisAppInterface