docs: def read_metadata(self, symbol):
          '''
          Reads user defined metadata out for the given symbol
  
          Parameters
          ----------
          symbol: str
              symbol for the given item in the DB
  
          Returns
          -------
          ?
          '''
          sym = self._get_symbol_info(symbol)
          if not sym:
              raise NoDataFoundException("Symbol does not exist.")
          x = self._symbols.find_one({SYMBOL: symbol})
          return x[USERMETA] if USERMETA in x else None