Getting error while starting the action server after upgrading rasa to latest version

@bparikh99 Here it is

from typing import Any, Text, Dict, List
from rasa_core_sdk import Action
from rasa_core_sdk import Tracker
from rasa_core_sdk.events import SlotSet
from rasa_sdk.executor import CollectingDispatcher


class MedicalNecessity(Action):
    def name(self) -> Text:
        return "action_necessity"

    def run(self, dispatcher: CollectingDispatcher,
            tracker: Tracker,
            domain: Dict[Text, Any]) -> List[Dict[Text, Any]]:
        incident_no = tracker.get_slot('incident_no')

        # from database medical necessity reason is fetched and stored in 'reason' variable
        reason = 'xyz'

        bot_response = " For {} incident number the medical necessity reason is {}".format(incident_no, reason)

        dispatcher.utter_message(text=bot_response)
        return [SlotSet('incident_no', incident_no)]


class ServiceLevel(Action):

    def name(self) -> Text:
        return "action_service"

    def run(self, dispatcher: CollectingDispatcher,
            tracker: Tracker,
            domain: Dict[Text, Any]) -> List[Dict[Text, Any]]:
        incident_no = tracker.get_slot('incident_no')

        # from database service level is fetched and stored in 'level' variable
        level = 123

        bot_response = " For {} incident number the level of service is {}".format(incident_no, level)

        dispatcher.utter_message(text=bot_response)
        return [SlotSet('incident_no', incident_no)]


class NecessityAndService(Action):

    def name(self) -> Text:
        return "action_necessity_service"

    def run(self, dispatcher: CollectingDispatcher,
            tracker: Tracker,
            domain: Dict[Text, Any]) -> List[Dict[Text, Any]]:
        incident_no = tracker.get_slot('incident_no')

        # from database medical necessity reason is fetched and stored in 'reason' variable
        # service level is fetched and stored in 'level' variable

        reason = 'abc'
        level = 123

        bot_response = " For {} incident number the medical necessity reason is {} and level of service is {}".format(
            incident_no, reason, level)

        dispatcher.utter_message(text=bot_response)
        return [SlotSet('incident_no', incident_no)]