docs: def get_value(self, subject=None, predicate=None, object_=None):
          """Returns the first triple value matching the given subject,
          predicate, and/or object"""
  
          for triple in self.triples:
  
              # Filter out non-matches
              if (subject and triple['subject'] != subject) or \
                 (predicate and triple['predicate'] != predicate) or \
                 (object_ and triple['object'] != object_):  # pragma: no cover
                  continue
  
              # Return the first found.
              return triple
  
          return None