creates a calendar to be used by the base date classes (-> ^Calendar (calendar (Date. 0) (TimeZone/getTimeZone “GMT”)) (.getTime)) => #inst “1970-01-01T00:00:00.000-00:00”

accesses the default timezone as a string

(default-timezone) ;; getter => “Asia/Ho_Chi_Minh”

(default-timezone “GMT”) ;; setter => “GMT”

accesses the default type for datetime

(default-type) ;; getter => clojure.lang.PersistentArrayMap

(default-type Long) ;; setter => java.lang.Long

returns the current timezone as a string

(local-timezone) => “Asia/Ho_Chi_Minh”