'Test color_rgb_to_hex.'

def test_color_rgb_to_hex(self):

    assert (color_util.color_rgb_to_hex(255, 255, 255) == 'ffffff')
    assert (color_util.color_rgb_to_hex(0, 0, 0) == '000000')
    assert (color_util.color_rgb_to_hex(51, 153, 255) == '3399ff')
