def trim_middle(arbitrary_string: str, max_length: int) -> str:
    """
    Trim down strings to max_length by cutting out the middle.
    This assumes that the most "interesting" bits are toward
    the beginning and the end.

    Adds a highly unusual '✂✂✂' in the middle where characters
    were stripped out, to avoid not realizing about the stripped
    info.
    """
    # candidate for moving to eth-utils, if we like it
    size = len(arbitrary_string)
    if size <= max_length:
        return arbitrary_string
    else:
        half_len, is_odd = divmod(max_length, 2)
        first_half = arbitrary_string[:half_len - 1]
        last_half_len = half_len - 2 + is_odd
        if last_half_len > 0:
            last_half = arbitrary_string[last_half_len * -1:]
        else:
            last_half = ''
        return f"{first_half}✂✂✂{last_half}"