text: #!/usr/bin/env python
  
  import ZODB
  import ZODB.FileStorage
  import transaction
  import custom_class_zodb
  
  filestorage = ZODB.FileStorage.FileStorage('zodb_filestorage.db')
  db = ZODB.DB(filestorage)
  conn = db.open()
  
  root = conn.root()
  noah = root['noah']
  print("BEFORE WITHDRAWAL")
  print("=================")
  print(noah)
  jeremy = root['jeremy']
  print(jeremy)
  print("-----------------")
  
  transaction.begin()
  noah.withdraw(300)
  jeremy.deposit(300)
  transaction.commit()
  
  print("AFTER WITHDRAWAL")
  print("================")
  print(noah)
  print(jeremy)
  print("----------------")
  
  conn.close()
  