Math magic methods

Below you can see the class Account. It has 2 instance attributes, account_id and amount, as well as some methods.

class Account:
    def __init__(self, account_id, amount):
        self.account_id = account_id
        self.amount = amount

    def __iadd__(self, other):
        self.amount += other.amount
        return self

    def __eq__(self, other):
        return ((self.account_id == other.account_id) and 
                (self.amount == other.amount))

We've created two instances of the class Account:

account1 = Account("acc0000927", 999.99)
account2 = Account("acc0083972", 1564.26)

Which of the following lines of code will work?