Write a function sum_of_ends that takes a list of numbers as an input parameter and: if the list is empty, returns 0 if the list is not empty, returns the sum of the first element (at index 0) and the last element (at index length - 1) Note that for a list with only one element, the first element and the last element would be the same one element in the list and thus the function should return the sum of the element with itself. ex: If a