code: def to_dict(self):
      questions = [q.to_dict() for q in self.questions]
      ret = {"qas": questions, "context": self.doc_text}
      return ret
  
imports: from typing import List, Union
label_desc: Use image node_id 2 for calling the QAInput obj's underlying member method code with example usage: obj.to_dict() and returns: ret