def __repr__(self):
    return '{class_} "{label}" with {n} document buckets'.format(class_=self.__class__, label=self.label, n=len(self.document_buckets))
def __repr__(self):
    return '{class_} "{label}" with {n} document buckets'.format(class_=self.__class__, label=self.label, n=len(self.document_buckets))