docstr: Validate `pizza_s1_type` value.
docstr_tok: ["Validate","`","pizza_s1_type","`","value","."]
code: def validate_pizza_s1_type(
      self,
      slot_value: Any,
      dispatcher: CollectingDispatcher,
      tracker: Tracker,
      domain: DomainDict,
  ) -> Dict[Text, Any]:
      """Validate `pizza_s1_type` value."""
      ALLOWED_PIZZA_TYPES = ["hải sản", "phô mai", "gà nướng"]
      if slot_value.lower() not in ALLOWED_PIZZA_TYPES:
          n = len(ALLOWED_PIZZA_TYPES)
          text = (
              f"Nhà hàng hiện tại có {n} loại: "
              + ", ".join(ALLOWED_PIZZA_TYPES).lower()
          )
          dispatcher.utter_message(text)
          return {"pizza_s1_type": None}
      return {"pizza_s1_type": slot_value}
  
file_path: underthesea/examples/chatbot/order_pizza_simple/actions/actions.py
imports: from typing import Text, Dict, Any
  from rasa_sdk import FormValidationAction, Tracker
  from rasa_sdk.executor import CollectingDispatcher
  from rasa_sdk.types import DomainDict
label_desc: Use image node_id 2 for calling the ValidationSimplePizzaForm obj's underlying member method code with example usage: obj.validate_pizza_s1_type(slot_value, dispatcher, tracker, domain) and returns: dict, dict