interpreter pattern we begin by creating just the stubs based on the grammar we defined earlierclass tab(object)pass class item(object)pass class customer(object)pass class discount(object)pass class rule(object)pass class customertype(object)pass class itemtype(object)pass class conditions(object)pass class condition(object)pass class timecondition(object)pass class dayofweek(object)pass class time(object)pass class hours(object)pass class hourtens(object)pass