I have a data frame with XY values which I would like to plot in a scatter plot. I would like to create groups which have a same XY values and apply the same color in the plot:

```
df = pd.DataFrame({'X': [1.1, 1.1, 5.5, 5.5, 5.5,10.1],
                   'Y': [3.7, 3.7, 5.6, 5.6, 5.6, 3.2],
                   'ID': ['ID1', 'ID2','ID3','ID4','ID5', 'ID6'})

X        Y         ID         color (hex or RGB)
1.1      3.7       ID1        0,255,255
1.1      3.7       ID2        0,255,255
5.5      5.6       ID3        255,0,255
5.5      5.6       ID4        255,0,255
5.5      5.6       ID5        255,0,255
10.1     3.2       ID6        0,0,255

```

How to map a color for each XY group?