Passing argument from a list

Question

I have a function that I'm using and I need to pass it a list of arguments, however, it gives an error when I try to pass the list because it can't hash.

The function in question here is the values() method on a Django Queryset, but I think this is a more general python question.

So I have:

values_list = ['arg1', 'arg2', 'arg3']
models.MyModel.objects.values(values_list).all()

This gives an error unhashable type: 'list' when i try to run the code. Assuming that I can't alter the values method, how can I add this list to the arguments list in the normal manner?

for arg in values_list:
  queryset = MyModel.objects.values(arg)

Answer 1

you need to use list unpacking

models.MyModel.objects.values(*values_list).all()

(note the asterisk)

Answer 2

can you use a tuple instead of a list? a tuple is hashable.

Answer 3

It makes sense to make values_list as a tuple instead of a list, but if you can't alter the values method, then list unpacking is the way to go.