code: def __init__(self, dbFilePath):
      self.__instrumentIds = {}
  
      # If the file doesn't exist, we'll create it and initialize it.
      initialize = False
      if not os.path.exists(dbFilePath):
          initialize = True
      self.__connection = sqlite3.connect(dbFilePath)
      self.__connection.isolation_level = None  # To do auto-commit
      if initialize:
          self.createSchema()
  
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 1 to create a new Database object from inherited base classes: dbfeed with example: obj = Database(dbFilePath)