docs: def delete_link(link_id, purge_data,**kwargs):
      """
          Remove link from DB completely
          If there are attributes on the link, use purge_data to try to
          delete the data. If no other resources link to this data, it
          will be deleted.
      """
      user_id = kwargs.get('user_id')
      try:
          link_i = db.DBSession.query(Link).filter(Link.id == link_id).one()
      except NoResultFound:
          raise ResourceNotFoundError("Link %s not found"%(link_id))
  
      group_items = db.DBSession.query(ResourceGroupItem).filter(
                                                      ResourceGroupItem.link_id==link_id).all()
      for gi in group_items:
          db.DBSession.delete(gi)
  
      if purge_data == 'Y':
          _purge_datasets_unique_to_resource('LINK', link_id)
  
      log.info("Deleting link %s, id=%s", link_i.name, link_id)
  
      link_i.network.check_write_permission(user_id)
      db.DBSession.delete(link_i)
      db.DBSession.flush()