code: def set_page_artid(self, page_start=None, page_end=None, artid=None):
          
          if page_end and not page_start:
              raise ValueError('End_page provided without start_page')
  
          self._ensure_reference_field('publication_info', {})
          publication_info = self.obj['reference']['publication_info']
          if page_start:
              publication_info['page_start'] = page_start
          if page_end:
              publication_info['page_end'] = page_end
          if artid:
              publication_info['artid'] = artid
docs: Add artid, start, end pages to publication info of a reference.
  
          Args:
              page_start(Optional[string]): value for the field page_start
              page_end(Optional[string]): value for the field page_end
              artid(Optional[string]): value for the field artid
  
          Raises:
              ValueError: when no start_page given for an end_page