docs: def read_audit_log(self, symbol=None):
          """
          Reads the audit log
  
          Parameters
          ----------
          symbol: str
              optionally only retrieve specific symbol's audit information
  
          Returns
          -------
          list of dicts
          """
          if symbol:
              return [x for x in self._audit.find({'symbol': symbol}, {'_id': False})]
          return [x for x in self._audit.find({}, {'_id': False})]