But in that case, either your code is evidently in a branch where the list will have one item -- as in your example -- in which case the context makes it clear.

But in that case, either your code is evidently in a branch where the list will have one item -- as in your example -- in which case the context makes it clear. And if there's no context, such as in a nested function call, then at some point you should be passing that lone list item into a function which takes the item as an argument.