convent hex color to tuple
    "#ffffff"   ->  (255, 255, 255)
    "#ffff00ff" ->  (255, 255, 0, 255)

def hex_color_to_tuple(hex):
    """ convent hex color to tuple
    "#ffffff"   ->  (255, 255, 255)
    "#ffff00ff" ->  (255, 255, 0, 255)
    """
    hex = hex[1:]
    length = len(hex) // 2
    return tuple(int(hex[i*2:i*2+2], 16) for i in range(length))