def format_filename(string):
    """
    Converts a string to an acceptable filename
        e.g. "Go! series - F1" into "Go_series_-_F1"

    Parameters:
        string (str): raw filename
    Returns:
        formatted_filename (str): formatted filename
    Raises:
    """
    # NOTE: Periods (.) and dashes (-) are allowed
    #       Spaces are converted to dashes
    formatted_filename = []
    symbols = "!@#$%^&*()+=[]\{}|:\";'<>?,/'"
    for c in string:
        if c == " ":
            formatted_filename.append("_")
        elif c in symbols:
            pass
        else:
            formatted_filename.append(c)

    formatted_filename = "".join(formatted_filename)

    return formatted_filename