Alternate Merge

You are given two singly non$-$dummy headed linked lists. Your task is to write a function alternate$\_$merge$($head$1,$ head$2)$ that takes the heads of the two linked lists and returns the head of a modified linked list with all the elements of the two lists in alternate order. It is guaranteed that alternate placement is always possible. Your resulting linked list will always start with the head of linked list $1.$

$\backslash$table$[[$Input$,$Output$],[$List$1$: $126811$ None,$15276389$