Antoon Pardon <apardon at forel.vub.ac.be> writes:
> Two guidelines can make it easier for a programmer to do this.
>
> 1) Put a copy in the dictionary, so that mutating the original
> object won't affect what is in the dictonary.
What's supposed to happen here?
a = [1,2,3]
d[a] = 9
a.append(4)
print d[a]
It doesn't sound like good dictionary semantics to me.