I think you're just testing your class wrong;
`Example[x]`

should be
`doodads[x]`

.

```
doodads = []
doodads.append(Example("red",5,10))
doodads.append(Example("red",8,9))
doodads.append(Example("blue",20,15))
doodads.append(Example("green",2,5))
doodads.append(doodads[0] * doodads[3]) #blue
doodads.append(doodads[3] * doodads[4]) #red
```

Output:

```
red weighing 5 grams. Value =
10.000000 points. S/N= 1001
red weighing 8 grams. Value = 9.000000 points.
S/N= 1002
blue weighing 20 grams. Value = 15.000000 points.
S/N= 1003
green weighing 2 grams. Value = 5.000000 points.
S/N= 1004
blue weighing 5 grams. Value = 7.000000 points.
S/N= 1005
red weighing 5 grams. Value = 6.000000 points.
S/N= 1006
```