기본 사용법¹⁾

# test_wallet.py
 
@pytest.fixture
def my_wallet():
    '''Returns a Wallet instance with a zero balance'''
    return Wallet()
 
@pytest.mark.parametrize("earned,spent,expected", [
    (30, 10, 20),
    (20, 2, 18),
])
def test_transactions(my_wallet, earned, spent, expected):
    my_wallet.add_cash(earned)
    my_wallet.spend_cash(spent)
    assert my_wallet.balance == expected