Question

I have multiple lists of tuples eg

[([1, 2, 3, 4], 2), ([5, 6, 7], 3)]

that I would like to have as keys to a dictionary (so each key in my dictionary would be a list of tuples).

Unfortunately, according to the TypeError I’m getting (unhashable type: list), it seems that python doesn’t like hashing lists. All of the elements in my list of tuples are ints (if that makes an difference). Any suggestions on what I can do? Thanks!

Answer 1

>>> def nested_lists_to_tuples(ls):
    return tuple(nested_lists_to_tuples(l) if isinstance(l, (list, tuple)) else l for l in ls)

>>> nested_lists_to_tuples([([1,2,3,4],2),([5,6,7],3)])
(((1, 2, 3, 4), 2), ((5, 6, 7), 3))

Then just use that returned value as your key. Note that I did it this way so you could support even more deeply nested mixes of tuples and lists, like [([1,(2, [3, 4, [5, 6, (7, 8)]]), 3, 4], 2), ([5, 6, 7], 3)]:

>>> nested_lists_to_tuples([([1, (2, [3, 4, [5, 6, (7, 8)]]), 3, 4], 2), ([5, 6, 7], 3)])
(((1, (2, (3, 4, (5, 6, (7, 8)))), 3, 4), 2), ((5, 6, 7), 3))

There may possibly be a simpler way to do this, though.