code: def __addInstrument(self, instrument):
      ret = self.__connection.execute(
          "insert into instrument (name) values (?)", [instrument]
      )
      return ret.lastrowid
  
imports: from pyalgotrade.barfeed import dbfeed
  from pyalgotrade.barfeed import membf
  from pyalgotrade import bar
  from pyalgotrade.utils import dt
  import sqlite3
  import os
label_desc: Use image node_id 3 for calling the Database obj's underlying member method code with example usage: obj.__addInstrument(instrument) and returns: ret