old_contents: import threading
  from zaifapi.impl import ZaifPublicApi
  from zaifbot.bot_common.config.config_object import *
  from zaifbot.bot_common.config.property import ApiKeys, Event, System
  
  
  
  def load_config():
      return _ConfigLoader()
  
  
  def _get_current_last_price(currency_pairs):
      api = ZaifPublicApi()
      return api.last_price(currency_pairs)['last_price']
  
  
  def _read_config():
      return Config(SystemValue(), ApiKeysValue(), EventValue())
  
  
  class _ConfigLoader:
      _instance = None
      _lock = threading.Lock()
      _start_time_last_price = None
  
      def __new__(cls):
          with cls._lock:
              if cls._instance is None:
                  cls._instance = super().__new__(cls)
                  config_json = _read_config()
                  system = System(config_json)
                  cls._start_time_last_price = _get_current_last_price(system.currency_pair)
          return cls._instance
  
      def __init__(self):
          config_json = _read_config()
          self._api_keys = ApiKeys(config_json)
          self._system = System(config_json)
          self._event = Event(config_json)
  
      @property
      def api_keys(self):
          return self._api_keys
  
      @property
      def system(self):
          return self._system
  
      @property
      def event(self):
          return self._event
  
      @property
      def start_time_last_price(self):
          return self._start_time_last_price
  
new_contents: import threading
  from zaifapi.impl import ZaifPublicApi
  from zaifbot.bot_common.config.config_object import *
  from zaifbot.bot_common.config.property import ApiKeys, Event, System
  
  
  
  def load_config():
      return _ConfigLoader()
  
  def _read_config():
      return Config(SystemValue(), ApiKeysValue(), EventValue())
  
  
  class _ConfigLoader:
      _instance = None
      _lock = threading.Lock()
  
      def __new__(cls):
          with cls._lock:
              if cls._instance is None:
                  cls._instance = super().__new__(cls)
          return cls._instance
  
      def __init__(self):
          config_json = _read_config()
          self._api_keys = ApiKeys(config_json)
          self._system = System(config_json)
          self._event = Event(config_json)
  
      @property
      def api_keys(self):
          return self._api_keys
  
      @property
      def system(self):
          return self._system
  
      @property
      def event(self):
          return self._event
  
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