def bookWS(symbols=None, on_data=None):
    '''https://iextrading.com/developer/docs/#book51'''
    symbols = _strToList(symbols)
    sendinit = ({'symbols': symbols, 'channels': ['book']},)
    return _stream(_wsURL('deep'), sendinit, on_data)
def bookWS(symbols=None, on_data=None):
    '''https://iextrading.com/developer/docs/#book51'''
    symbols = _strToList(symbols)
    sendinit = ({'symbols': symbols, 'channels': ['book']},)
    return _stream(_wsURL('deep'), sendinit, on_data)
def bookWS ( symbols = None , on_data = None ) : symbols = _strToList ( symbols ) sendinit = ( { 'symbols' : symbols , 'channels' : [ 'book' ] } , ) return _stream ( _wsURL ( 'deep' ) , sendinit , on_data )
https://iextrading.com/developer/docs/#book51
https : // iextrading . com / developer / docs / #book51