在列表中找到与其他元素不同的元素的最pythonic方法是什么？

Suppose we have a list with unknown size and there is an element in the list that is different with other elements but we don't know the index of the element. the list only contains numerics and is fetched from a remote server and the length of the list and the index of the different element is changed every time. what is the most pythonic way to find that different element? I tried this but I'm not sure if it's the best solution.Suppose we have a list with unknown size and th