class_docstr: With the ``EdgesOnly`` policy, only graph edges are able to be selected and
  inspected. There is no selection or inspection of graph nodes.
code: def __init__(self, *args, **kwargs) -> None:
      super().__init__(*args, **kwargs)
  
imports: from __future__ import annotations
  import logging
  from ..core.has_props import abstract
  from ..core.properties import Dict, Either, Float, Instance, Int, Len, Seq, String
  from ..model import Model
  from .expressions import CoordinateTransform
label_desc: Use image node_id 1 to create a new EdgesOnly object from inherited base classes: GraphHitTestPolicy with example: obj = EdgesOnly()