code: def get_bbands(self, symbol, interval='daily', time_period=20,  series_type='close',
                     nbdevup=None, nbdevdn=None, matype=None):
          
          _FUNCTION_KEY = "BBANDS"
          return _FUNCTION_KEY, 'Technical Analysis: BBANDS', 'Meta Data'
docs: Return the bollinger bands values in two
          json objects as data and meta_data. It raises ValueError when problems
          arise
  
          Keyword Arguments:
              symbol:  the symbol for the equity we want to get its data
              interval:  time interval between two conscutive values,
                  supported values are '1min', '5min', '15min', '30min', '60min', 'daily',
                  'weekly', 'monthly' (default 'daily'
              series_type:  The desired price type in the time series. Four types
                  are supported: 'close', 'open', 'high', 'low' (default 'close')
              nbdevup:  The standard deviation multiplier of the upper band. Positive
                  integers are accepted as default (default=2)
              nbdevdn:  The standard deviation multiplier of the lower band. Positive
                  integers are accepted as default (default=2)
              matype :  Moving average type. By default, matype=0.
                  Integers 0 - 8 are accepted (check  down the mappings) or the string
                  containing the math type can also be used.
  
                  * 0 = Simple Moving Average (SMA),
                  * 1 = Exponential Moving Average (EMA),
                  * 2 = Weighted Moving Average (WMA),
                  * 3 = Double Exponential Moving Average (DEMA),
                  * 4 = Triple Exponential Moving Average (TEMA),
                  * 5 = Triangular Moving Average (TRIMA),
                  * 6 = T3 Moving Average,
                  * 7 = Kaufman Adaptive Moving Average (KAMA),
                  * 8 = MESA Adaptive Moving Average (MAMA)