Transforms a PNG file in a QIcon

    Looks for a file named <keyword>.png in the "icons" directory

    If file does not exist, returns None

def get_icon(keyword):
    """
    Transforms a PNG file in a QIcon

    Looks for a file named <keyword>.png in the "icons" directory

    If file does not exist, returns None
    """

    filename = a99.get_path( "icons", keyword + ".png")
    if not os.path.isfile(filename):
        raise FileNotFoundError("File '{}' does not exist".format(filename))
    return QIcon(filename)