text: import configparser
  from linebot import (
      LineBotApi, WebhookHandler
  )
  
  
  class Singleton(type):
      _instances = {}
  
      def __call__(cls, *args, **kwargs):
          if cls not in cls._instances:
              cls._instances[cls] = super(
                  Singleton, cls).__call__(*args, **kwargs)
          return cls._instances[cls]
  
  class Initialization(metaclass=Singleton):
      SETTING_FILE = "setting.config"
      def __init__(self, file=SETTING_FILE):
          self.config = configparser.ConfigParser()
          self.check_file(file)
          self.Channel_Access_Token = self.config['LINE_BOT_CONGIGURE']['Channel_Access_Token']
          self.Channel_Secret = self.config['LINE_BOT_CONGIGURE']['Channel_Secret']
          self.Channel_User_ID = self.config['LINE_BOT_CONGIGURE']['Channel_User_ID']
          self.handler = None
          self.line_bot_api = None
          self.line_bot_init()
  
      def check_file(self, file):
          self.config.read(file)
          if not self.config.sections():
              raise configparser.Error('setting.config not exists')
  
      def line_bot_init(self):
          self.handler = WebhookHandler(self.Channel_Secret)
          self.line_bot_api = LineBotApi(self.Channel_Access_Token)
  