Creating a package
CG-USER(6): (defpackage :my-first-package)
#<The MY-FIRST-PACKAGE package>
CG-USER(7): (package-use-list
(find-package :my-first-package))
(#<The COMMON-LISP package>)
CG-USER(8): (in-package :my-first-package)
#<The MY-FIRST-PACKAGE package>
MY-FIRST-PACKAGE(9): (defun my-function (a b)
MY-FIRST-PACKAGE(10): (my-function 2 3)