code: def export_modified_data(self):
          
          # TODO: why None? Try to get a better flag
          result = {key: None for key in self.__deleted_fields__}
  
          for key, value in self.__modified_data__.items():
              if key in result.keys():
                  continue
              try:
                  result[key] = value.export_modified_data()
              except AttributeError:
                  result[key] = value
  
          for key, value in self.__original_data__.items():
              if key in result.keys():
                  continue
              try:
                  if value.is_modified():
                      result[key] = value.export_modified_data()
              except AttributeError:
                  pass
  
          return result
docs: Get the modified data