code: def ld(v):
      """Load variable operator."""
      if isinstance(v, Undefined):
          return v.read()
      if hooks._DISPATCH.detect_overload_ld(v):
          return hooks._DISPATCH.ld(v)
      return v
  
file_path: DALI/dali/python/nvidia/dali/_autograph/operators/variables.py
imports: from nvidia.dali._autograph.utils import hooks
label_desc: Use image node_id 1 for calling a global function with example usage: ld(v) and returns: v, v, hooks