4.5. Saving and Loading

def visits() -> DialogueFlow:
    transitions = {
        'state': 'start',
        '`It\'s your` #VISITS `visit!`': 'end'
    }

    macros = {
        'VISITS': MacroVisits()
    }

    df = DialogueFlow('start', end_state='end')
    df.load_transitions(transitions)
    df.add_macros(macros)
    return df

class MacroVisits(Macro):
    def run(self, ngrams: Ngrams, vars: Dict[str, Any], args: List[Any]):
        vn = 'VISITS'
        if vn not in vars:
            vars[vn] = 1
            return 'first'
        else:
            count = vars[vn] + 1
            vars[vn] = count
            match count:
                case 2: return 'second'
                case 3: return 'third'
                case default: return '{}th'.format(count)

def save(df: DialogueFlow, varfile: str):
    df.run()
    d = {k: v for k, v in df.vars().items() if not k.startswith('_')}
    pickle.dump(d, open(varfile, 'wb'))

save(visits(), 'resources/visits.pkl')

def load(df: DialogueFlow, varfile: str):
    d = pickle.load(open(varfile, 'rb'))
    df.vars().update(d)
    df.run()
    save(df, varfile)