code: def _formatExternalIdentifier(self, element, element_type):
          
          if "http" not in element['database']:
              term = "{}:{}".format(element['database'], element['identifier'])
              namespaceTerm = self._toNamespaceURL(term)
          else:
              namespaceTerm = "{}{}".format(
                  element['database'], element['identifier'])
          comparison = '?{} = <{}> '.format(element_type, namespaceTerm)
          return comparison
docs: Formats a single external identifier for query