def closest_pentameter_patterns(self, scansion: str) -> List[str]:
        """
        Find the closest group of matching valid pentameter patterns.

        :return: list of the closest valid pentameter patterns; only candidates with a matching
        length/number of syllables are considered.

        >>> print(MetricalValidator().closest_pentameter_patterns('--UUU--UU-UUX'))
        ['---UU--UU-UUX']
        """
        return self._closest_patterns(self.VALID_PENTAMETERS, scansion)