What does this code write (§3.2)?

class Account:
    def __init__(self, owner, balance):
        self._owner = owner
        self._balance = balance
    def deposit(self, amount):
        self._balance += amount
    def balance(self):
        return self._balance
accounts = [Account('ann', 10), Account('bob', 20)]
first = accounts[0]
accounts[0] = Account('cat', 30)
first.deposit(5)
accounts[1].deposit(5)
print(first.balance(), accounts[0].balance(), accounts[1].balance())

Wat skryf hierdie kode?