我正在尝试创建一个名为"common_ancestor()“的函数,该函数接受两个输入:第一个输入是字符串分类名列表,第二个输入是系统发育树字典。lists where i can cross reference all elements from the first list to every other list to find a common ancestor" print(common_ancestor([’Hominoidea’, ’Pan troglodytes’,’Lorisifor