def METHOD_NAME(self):
    """
    Too short sequences are simply removed. This could be tuned.
    """
    init_size = len(self)
    indices = self.lengths > 11
    self.token_ids = self.token_ids[indices]
    self.lengths = self.lengths[indices]
    new_size = len(self)
    logger.info(f"Remove {init_size - new_size} too short (<=11 tokens) sequences.")