Do not use any pre$-$defined Prolog list predicates in answering this question.

Define a Prolog predicate blend$($X$,$Y$,$Z$)$ which is true only if Z is a list that results from

selecting elements from lists X and Y in strict alternation, as shown in these examples: blend$([1,2,3],$

$[101,201],[1,101,2,201,3])$ is true. blend$([1,2],[101,201,301],[1,101,2,201,301])$ is

true. blend$([1,2],[],[1,2])$ is true. blend$([1,2],[101,201,301,401],$ Z$)$ results in Z $=[1,101,2,201,301,401].$