code: def _load_xml(self):
          
          if self._xml is not None:
              return
          matcher = "\[(?:Normal|Conditional) Substitution\(index=(\d+), type=\d+\)\]"
          self._xml = re.sub(matcher, "{\\1:}",
                             self._template_node.template_format().replace("{", "{{").replace("}", "}}"))
docs: TODO(wb): One day, nodes should generate format strings
            instead of the XML format made-up abomination.