code: def bookSSE(symbols=None, on_data=None, token='', version=''):
      '''Book shows IEX’s bids and asks for given symbols.
  
      https://iexcloud.io/docs/api/#deep-book
  
      Args:
          symbols (string); Tickers to request
          on_data (function): Callback on data
          token (string); Access token
          version (string); API version
  
      '''
      return _runSSE('book', symbols, on_data, token, versionf bookSSE(symbols=None, on_data=None, token='', version=''):
      '''Book shows IEX’s bids and asks for given symbols.
  
      https://iexcloud.io/docs/api/#deep-book
  
      Args:
          symbols (string); Tickers to request
          on_data (function): Callback on data
          token (string); Access token
          version (string); API version
  
      '''
      return _runSSE('book', symbols, on_data, token, version)
docs: Book shows IEX’s bids and asks for given symbols.
  
      https://iexcloud.io/docs/api/#deep-book
  
      Args:
          symbols (string); Tickers to request
          on_data (function): Callback on data
          token (string); Access token
          version (string); API version