text: 
  # return code
  ERR_SUCCESS = 0
  ERR_WEB_ERROR = -1
  ERR_GET_STOCK_ERROR = -2
  
  # API
  yahoo_api_v8_template = 'https://query1.finance.yahoo.com/v8/finance/chart/{symbol}?includePrePost=false&interval={interval}&range={range}'
  
  # common function
  