You are managing a grocery store's system, and you need to maintain **decision-making** for the inventory, track prices, and perform checks to determine if actions like restocking or removing items from the inventory are needed based on their price or stock. 

# Unit tests (test_main.py) â strongly simplified and flexible

import unittest
import importlib
import io
from contextlib import redirect_stdout
import user_code


def _dynamic_test(test_case, condition, success_message, failure_message):
    if condition:
        test_case._testMethodName = success_message
        test_case.assertTrue(True, success_message)
    else:
        test_case._testMethodName = failure_message
        test_case.fail(failure_message)


class TestGroceryInventorySimplified(unittest.TestCase):

    def normalize_text(self, text: str) -> str:
        return " ".join(text.lower().split())

    # Core state checks

    def test_eggs_price_reduced(self):
        importlib.reload(user_code)
        price = user_code.grocery_inventory["Eggs"][1]
        _dynamic_test(
            self,
            abs(price - 4.50) < 1e-9,
            "Eggs price reduced to 4.50",
            f"Expected Eggs price 4.50, got {price}",
        )

    def test_tomatoes_added(self):
        importlib.reload(user_code)
        inv = user_code.grocery_inventory
        _dynamic_test(
            self,
            "Tomatoes" in inv and inv["Tomatoes"] == ("Produce", 1.20, 30),
            "Tomatoes added with correct details",
            "Tomatoes missing or incorrect",
        )

    def test_milk_stock_increased(self):
        importlib.reload(user_code)
        stock = user_code.grocery_inventory["Milk"][2]
        _dynamic_test(
            self,
            stock == 28,
            "Milk stock increased by 20 to 28",
            f"Expected Milk stock 28, got {stock}",
        )

    def test_apples_remain(self):
        importlib.reload(user_code)
        _dynamic_test(
            self,
            "Apples" in user_code.grocery_inventory,
            "Apples remain in inventory at price <= 2",
            "Apples should not have been removed",
        )

    # Light output checks (no strict punctuation)

    def test_output_messages_present(self):
        f = io.StringIO()
        with redirect_stdout(f):
            importlib.reload(user_code)
        out = self.normalize_text(f.getvalue())

        expected_phrases = [
            "eggs are too expensive, reducing the price by $1.",
            "inventory after adding tomatoes:",
            "milk needs to be restocked. increasing stock by 20 units.",
            "updated inventory:",
        ]
        for phrase in expected_phrases:
            _dynamic_test(
                self,
                phrase in out,
                f"Output includes: {phrase}",
                f"Expected output to include: {phrase}",
            )


if __name__ == "__main__":
    unittest.main()

test_main.py

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Challenge: Pricing Adjustment Capstone

解答