Cenário 3 do artigo: https://elyssonmr.com/blog/posts/20241231_tests_hints/

helpers.py

from scenario3.price_client import get_price


def retrieve_prices(products_id: list[str]) -> dict[str, float]:
    prices = []
    for product_id in products_id:
        price = get_price(product_id)
        prices.append({'product_id': product_id, 'price': price})

    return prices

price_client.py

def get_price(product_id: str) -> float:
    # should consult price from a API
    pass

test_retrieve_prices.py

from unittest.mock import patch, call

import pytest

from scenario3.helpers import retrieve_prices


@pytest.fixture
def mock_get_price():
    with patch('scenario3.helpers.get_price') as patched:
        yield patched


def test_should_retrieve_prices(mock_get_price):
    mock_get_price.side_effect = [10.5, 9.83]
    products_ids = ['123456', '654321']

    products_prices = retrieve_prices(products_ids)

    assert products_prices == [{
        'product_id': '123456',
        'price': 10.5,
    }, {
        'product_id': '654321',
        'price': 9.83,
    }]
    mock_get_price.assert_has_calls([call('123456'), call('654321')])
    assert mock_get_price.call_count == 2