Write a Lisp function which takes two lists, list1 and list2, and returns true if list1 is a prefix of list2.

For example, if the function name is IsPrefix, when you call

(IsPrefix (2) (2 3 4)), it returns true.

(IsPrefix NIL (2 3 4)), it returns true.

(IsPrefix (2 3 44) (2 3 44 100 200)), it returns true.

(IsPrefix (2 3 44) (2 3 44)), it returns true.

(IsPrefix (2) (300 400 2)), it returns false.