docs: def _TemplateNamesToFiles(self, template_str):
          """Parses a string of templates into a list of file handles."""
          template_list = template_str.split(":")
          template_files = []
          try:
              for tmplt in template_list:
                  template_files.append(open(os.path.join(self.template_dir, tmplt), "r"))
          except:  # noqa
              for tmplt in template_files:
                  tmplt.close()
              raise
  
          return template_files