def string2rgba(cls, colorstring):
        """ Convert #RRGGBBAA to an (R, G, B, A) tuple """
        colorstring = colorstring.strip()
        if colorstring[0] == '#':
            colorstring = colorstring[1:]
        if len(colorstring) < 6:
            raise ValueError("input #%s is not in #RRGGBB format" % colorstring)
        r, g, b = colorstring[:2], colorstring[2:4], colorstring[4:6]
        a = 'ff'
        if len(colorstring) > 6:
            a = colorstring[6:8]
        r, g, b, a = [int(n, 16) for n in (r, g, b, a)]
        return (r, g, b, a)
Convert #RRGGBBAA to an (R, G, B, A) tuple