Hi, here's your problem today. This problem was recently asked by Twitter:

Given 3 sorted lists, find the intersection of those 3 lists.

Here's an example and some starter code.

```
def intersection(list1, list2, list3):
# Fill this in.
print(intersection([1, 2, 3, 4], [2, 4, 6, 8], [3, 4, 5]))
# [4]
```