code: def _get_el_to_normative(parent_elem, normative_parent_elem):
          
          el_to_normative = OrderedDict()
          if normative_parent_elem is None:
              for el in parent_elem:
                  el_to_normative[el] = None
          else:
              for norm_el in normative_parent_elem:
                  matches = [
                      el
                      for el in parent_elem
                      if el.get("TYPE") == norm_el.get("TYPE")
                      and el.get("LABEL") == norm_el.get("LABEL")
                  ]
                  if matches:
                      el_to_normative[matches[0]] = norm_el
                  else:
                      el_to_normative[norm_el] = None
          return el_to_normative
docs: Return ordered dict ``el_to_normative``, which maps children of
          ``parent_elem`` to their normative counterparts in the children of
          ``normative_parent_elem`` or to ``None`` if there is no normative
          parent. If there is a normative div element with no non-normative
          counterpart, that element is treated as a key with value ``None``.
          This allows us to create ``FSEntry`` instances for empty directory div
          elements, which are only documented in a normative logical structmap.