@staticmethod
def retrieve_predicates(statement):
    """Retrieve predicates with respective 'items' components

        :param statement: the dictionary to extract predicate values from
        :return: retrieval result as a string
        """
    predicates = 'any_of', 'all_of', 'one_of', 'none_of'
    for predicate in predicates:
        if predicate in statement:
            result = ', '.join(statement[predicate].get('items'))
            return '{0} ({1})'.format(predicate, result)
    raise ValueError('Predicates not found.')
