class_docstr: Represents a debugger-decorated graph.
docstr: Determine whether an input of an op is ref-type.
  
  Args:
    node: A `NodeDef`.
  
  Returns:
    A list of the arg names (as strs) that are ref-type.
docstr_tok: ["Determine","whether","an","input","of","an","op","is","ref-type",".","Args",":","node",":","A","`","NodeDef","`",".","Returns",":","A","list","of","the","arg","names","(","as","strs",")","that","are","ref-type","."]
code: def _get_ref_args(self, node):
      """Determine whether an input of an op is ref-type.
  
      Args:
        node: A `NodeDef`.
  
      Returns:
        A list of the arg names (as strs) that are ref-type.
      """
      op_def = op_def_registry.get(node.op)
      if op_def is None:
          return []
  
      ref_args = []
      for i, output_arg in enumerate(op_def.output_arg):
          if output_arg.is_ref:
              arg_name = (
                  node.name if i == 0 else ("%s:%d" % (node.name, i))
              )
              ref_args.append(arg_name)
      return ref_args
  
imports: from tensorflow.core.framework import graph_pb2
  from tensorflow.python.framework import op_def_registry
  from tensorflow.python.platform import tf_logging
label_desc: Use image node_id 3 for calling the DebugGraph obj's underlying member method code with example usage: obj._get_ref_args(node) and returns: ref_args, list