Итерация по элементам хэш-таблицы

(defparameter *my-hash* (make-hash-table))
; *MY-HASH*
(setf (gethash 'first-key *my-hash*) 'one)
; ONE
(setf (gethash 'second-key *my-hash*) 'two)
; TWO
(setf (gethash 'third-key *my-hash*) nil)
; NIL
(setf (gethash nil *my-hash*) 'nil-value)
; NIL-VALUE
(defun print-hash-entry (key value)
    (format t "The value associated with the key ~S is ~S~%" key value))
; PRINT-HASH-ENTRY
(maphash #'print-hash-entry *my-hash*)
; The value associated with the key FIRST-KEY is ONE
; The value associated with the key SECOND-KEY is TWO
; The value associated with the key THIRD-KEY is NIL
; The value associated with the key NIL is NIL-VALUE