def format_sequences_for_simulation(
    all_tokens: Sequence[Sequence[str]],
) -> str:
    """
    Format a list of lists of tokens into a string with each token marked as having an "unknown"
    activation, suitable for use in prompts.
    """
    return (
        "\n<start>\n"
        + "\n<end>\n<start>\n".join(
            [_format_tokens_for_simulation(tokens) for tokens in all_tokens]
        )
        + "\n<end>\n"
    )

    Format a list of lists of tokens into a string with each token marked as having an "unknown"
    activation, suitable for use in prompts.
    
neuron_explainer/activations/activation_records.py