GET LAST LIST ITEM

(define (not_ item)
   (
      cond ((EQ? item #f) #t)
            ( #t #f)


    )
)

(define (and_  item1 item2)

     (cond ((EQ? item1 #f) #f)
           ((EQ? item2 #f) #f)
     (#t #t)
     )

)

(define (or_ item1 item2)
        ( not_ (and_ (not_ item1) (not_ item2) ) )

)

(define (count_ lst len)

 (cond ((EQV? lst '() ) len  )
        ((not_ (PAIR? lst)) len )
        ( (= 1 1)  (
                    count_ (cdr lst  ) (+ len 1)

                           ))))


(define (get_by_index  array index)
    (cond ((= index 1)

                       (cond (( and_  (PAIR?  (car array))   (not_ (LIST? (car array))) )

                              array

                              )
                              ((LIST? array)  (car array) )
                              ((= 1 1) array)
                             )
                       )
          ((= 1 1) (get_by_index  (cdr array)  (  - index 1) ) )
    )
)


(define (calculete my_list)

     (cond ((and_  (not_ (LIST? my_list)) (not_ (PAIR? my_list))) "atom" )
           (( EQ? my_list '() ) '() )
           (( = 1 1)   (get_by_index my_list (count_ my_list 0))  )

      )
  )

 (calculete  "ff")
  (calculete  '())
   (calculete  '(4 53 5345435 555))
    (calculete  '(3 5 53 6 7 4 3 . 5))
      (calculete  '(3 5 53 6 7 (4 3  5 6 . 6) ))
      (calculete  '( 3 . 5))