code: def pre_processing(data, context):
      """
      Empty node as a starting node since the DAG doesn't support multiple start nodes
      """
      if data:
          text = data[0].get("data") or data[0].get("body")
          return [text]
      return None
  
label_desc: Use image node_id 1 for calling a global function with example usage: pre_processing(data, context) and returns: None, list