def complementary(hexcolor):
    """Returns complementary RGB color
    Example: complementaryColor('#FFFFFF') --> '#000000'
    """
    if hexcolor[0] == '#':
        hexcolor = hexcolor[1:]
    rgb = (hexcolor[0:2], hexcolor[2:4], hexcolor[4:6])
    comp = ['%02X' % (255 - int(a, 16)) for a in rgb]
    return '#' + ''.join(comp)