code: def fix_related_item_tag(dom):
      
      location = dom.match(
          "mods:mods",
          "mods:relatedItem",
          "mods:location"
      )
  
      if not location:
          return
      location = first(location)
  
      location.replaceWith(
          dhtmlparser.HTMLElement()
      )
  
      # remove whole <mods:relatedItem> tag, if there is nothing else left in it
      related_item = dom.match(
          "mods:mods",
          "mods:relatedItem"
      )
      related_item = first(related_item)
  
      if not related_item.getContent().strip():
          related_item.replaceWith(dhtmlparser.HTMLElement())
docs: Remove <mods:relatedItem> tag in case that there is only <mods:location>
      subtag.