def make_batches(tokens, batch_size):
    """
    Breaks a list into a list of lists each with batch_size elements.
    """
    if len(tokens) <= batch_size:
        return [tokens]
    else:
        batches = []
        while len(tokens) > 0:
            batches.append(tokens[:batch_size])
            tokens = tokens[batch_size:]
    return batches