old_contents: """Tools for handling items on a diagram."""
  from gaphas.segment import segment_tool
  from gaphas.tool import (
      hover_tool,
      item_tool,
      rubberband_tool,
      scroll_tool,
      view_focus_tool,
      zoom_tool,
  )
  
  import gaphor.diagram.diagramtools.connector
  import gaphor.diagram.diagramtools.grayout
  import gaphor.diagram.diagramtools.segment
  from gaphor.diagram.diagramtools.dropzone import drop_zone_tool
  from gaphor.diagram.diagramtools.placement import new_item_factory, placement_tool
  from gaphor.diagram.diagramtools.shortcut import shortcut_tool
  from gaphor.diagram.diagramtools.textedit import text_edit_tools
  from gaphor.diagram.diagramtools.txtool import transactional_tool
  
  
  def apply_default_tool_set(view, modeling_language, event_manager, rubberband_state):
      """The default tool set."""
      view.remove_all_controllers()
      view.add_controller(hover_tool(view))
      view.add_controller(
          *transactional_tool(
              segment_tool(view), item_tool(view), event_manager=event_manager
          )
      )
      view.add_controller(*text_edit_tools(view))
      view.add_controller(rubberband_tool(view, rubberband_state))
      view.add_controller(scroll_tool(view))
      view.add_controller(zoom_tool(view))
      view.add_controller(view_focus_tool(view))
      view.add_controller(shortcut_tool(view, modeling_language, event_manager))
  
  
  def apply_placement_tool_set(
      view, item_factory, modeling_language, event_manager, handle_index
  ):
      view.remove_all_controllers()
      view.add_controller(view_focus_tool(view))
      view.add_controller(
          *transactional_tool(
              placement_tool(view, item_factory, event_manager, handle_index),
              event_manager=event_manager,
          )
      )
      view.add_controller(drop_zone_tool(view, item_factory.item_class))
      view.add_controller(scroll_tool(view))
      view.add_controller(zoom_tool(view))
      view.add_controller(shortcut_tool(view, modeling_language, event_manager))
  
new_contents: """Tools for handling items on a diagram."""
  from gaphas.segment import segment_tool
  from gaphas.tool import (
      hover_tool,
      item_tool,
      rubberband_tool,
      scroll_tools,
      view_focus_tool,
      zoom_tool,
  )
  
  import gaphor.diagram.diagramtools.connector
  import gaphor.diagram.diagramtools.grayout
  import gaphor.diagram.diagramtools.segment
  from gaphor.diagram.diagramtools.dropzone import drop_zone_tool
  from gaphor.diagram.diagramtools.placement import new_item_factory, placement_tool
  from gaphor.diagram.diagramtools.shortcut import shortcut_tool
  from gaphor.diagram.diagramtools.textedit import text_edit_tools
  from gaphor.diagram.diagramtools.txtool import transactional_tool
  
  
  def apply_default_tool_set(view, modeling_language, event_manager, rubberband_state):
      """The default tool set."""
      view.remove_all_controllers()
      view.add_controller(hover_tool(view))
      view.add_controller(
          *transactional_tool(
              segment_tool(view), item_tool(view), event_manager=event_manager
          )
      )
      view.add_controller(*text_edit_tools(view))
      view.add_controller(rubberband_tool(view, rubberband_state))
      view.add_controller(*scroll_tools(view))
      view.add_controller(zoom_tool(view))
      view.add_controller(view_focus_tool(view))
      view.add_controller(shortcut_tool(view, modeling_language, event_manager))
  
  
  def apply_placement_tool_set(
      view, item_factory, modeling_language, event_manager, handle_index
  ):
      view.remove_all_controllers()
      view.add_controller(view_focus_tool(view))
      view.add_controller(
          *transactional_tool(
              placement_tool(view, item_factory, event_manager, handle_index),
              event_manager=event_manager,
          )
      )
      view.add_controller(drop_zone_tool(view, item_factory.item_class))
      view.add_controller(*scroll_tools(view))
      view.add_controller(zoom_tool(view))
      view.add_controller(shortcut_tool(view, modeling_language, event_manager))
  
subject: Use new scroll_tools