How to change key bindings for Calendar mode?

Question

How to change key-bindings for Calendar Mode only? I'm trying to do something like this:

; original bindings require pressing alt and shift simultaneously
; alt+shift change keyboard layout, so I cannot use those bindings
(define-key calendar-mode-map (kbd "M-]") 'calendar-forward-month)
(define-key calendar-mode-map (kbd "M-[") 'calendar-backward-month)

but calendar-mode-map is void. How can I get name of keymap of Calendar mode (or any arbitrary mode).

Answer 1

calendar-mode-map is void since it's not loaded yet:

(eval-after-load "calendar"
  `(progn
     (define-key calendar-mode-map (kbd "M-]") 'calendar-forward-month)
     (define-key calendar-mode-map (kbd "M-[") 'calendar-backward-month)))