def prettify_execute_intput(line_number, cmd, prompt_in):
    """Add additional formatting around a multiline command.

    Parameters
    ----------
    line_number : int or str
        Starting line number of input command.
    cmd : str
        The command to be executed.
    prompt_in : str
        The leader prompt string.

    Returns
    -------
    str
        Input command with additional formatting.
    """
    prompt = prompt_in.format(line_number)
    # Add continuation line, if necessary
    dots = (' ' * (len(prompt.rstrip()) - 4)) + '...: '
    return prompt + cmd.rstrip().replace('\n', '\n' + dots)