Load Stats at Startup

Define load_stats to read the saved stats file and restore the player's history

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save_stats writes the data. Now you need to read it back at startup so the player's history is restored.

There is one difference from load_questions: questions.json was already there when you wrote load_questions — you provided it. stats.json only exists after the first time the player quits. If you call open("stats.json", "r") before that file has been created, Python raises a FileNotFoundError and the program crashes.

You have already seen try/except in ask_question — it catches ValueError when the player types non-numeric input. The same pattern handles a missing file:

def load_stats():
    try:
        with open(STATS_FILE, "r") as f:
            return json.load(f)
    except FileNotFoundError:
        return {
            "games": 0,
            "best_score": 0,
            "best_total": 0,
            "total_correct": 0,
            "total_questions": 0,
        }

If the file exists, the try block succeeds and returns the saved stats. If it does not exist yet, FileNotFoundError is raised and the except block returns the default empty stats instead. Either way, STATS ends up as a valid dict.

Instructions

Define load_stats and use it to initialize STATS.

Below load_questions, define a function called load_stats with no parameters. Inside:
- Add a try: block. Inside it, open STATS_FILE in read mode ("r") using with open(...) as f: and return json.load(f).
- Add an except FileNotFoundError: block. Inside it, return a dict with all five keys set to 0: "games", "best_score", "best_total", "total_correct", "total_questions".
Replace STATS = { ... } (the entire dict literal below) with STATS = load_stats().

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import json

QUESTIONS_FILE = "questions.json"
STATS_FILE = "stats.json"

def load_questions():
    with open(QUESTIONS_FILE, "r") as f:
        return json.load(f)

# Step 1: define load_stats()

QUESTIONS = load_questions()
STATS = {  # Step 2: replace with STATS = load_stats()
    "games": 0,
    "best_score": 0,
    "best_total": 0,
    "total_correct": 0,
    "total_questions": 0,
}

def ask_question(q):
    print(q["text"])
    print()
    print(f"  1) {q['options'][0]}")
    print(f"  2) {q['options'][1]}")
    print(f"  3) {q['options'][2]}")
    print(f"  4) {q['options'][3]}")
    print()
    while True:
        answer_text = input("Your answer (1-4): ")
        try:
            answer = int(answer_text)
        except ValueError:
            print("Please enter 1, 2, 3, or 4.")
            continue
        if answer < 1 or answer > 4:
            print("Please enter 1, 2, 3, or 4.")
            continue
        break
    is_correct = answer == q["correct"]
    print()
    print(f"You answered: {answer}")
    if is_correct:
        print("Correct!")
    else:
        print(f"Wrong! The correct answer was option {q['correct']}.")
    return is_correct

def show_results(score, total):
    print(f"Score: {score}/{total}")
    if score == total:
        print("Perfect score!")
    elif score >= 2:
        print("Great job!")
    elif score >= 1:
        print("Not bad!")
    else:
        print("Keep practicing!")

def show_stats():
    if STATS["games"] == 0:
        print("No games played yet.")
        return
    print(f"Games played: {STATS['games']}")
    print(f"Best round: {STATS['best_score']}/{STATS['best_total']}")
    print(f"Total correct: {STATS['total_correct']} out of {STATS['total_questions']}")

def save_stats():
    with open(STATS_FILE, "w") as f:
        json.dump(STATS, f, indent=2)

def run_quiz(questions=QUESTIONS, num=None):
    if num is None:
        num = len(questions)
    score = 0
    streak = 0
    questions_for_round = questions[:num]
    total = len(questions_for_round)
    print(f"=== Python Quiz ({total} questions) ===")
    print()
    for q in questions_for_round:
        result = ask_question(q)
        if result:
            score = score + 1
            streak = streak + 1
            if streak >= 3:
                print(f"  Hot streak! ({streak} in a row)")
        else:
            streak = 0
    show_results(score, total)
    return score, total

while True:
    show_stats()
    print()
    categories = sorted(set(q["category"] for q in QUESTIONS))
    print("Categories: " + ", ".join(categories))
    category = input("Category (enter for all): ").strip()
    if category:
        pool = [q for q in QUESTIONS if q["category"] == category]
        if not pool:
            print("Category not found. Playing all.")
            pool = QUESTIONS
    else:
        pool = QUESTIONS
    try:
        num_input = input(f"How many questions? (1-{len(pool)}, enter for all): ").strip()
        if num_input:
            num = int(num_input)
        else:
            num = len(pool)
    except ValueError:
        num = len(pool)
    print()
    score, total = run_quiz(pool, num)
    STATS["games"] = STATS["games"] + 1
    STATS["total_correct"] = STATS["total_correct"] + score
    STATS["total_questions"] = STATS["total_questions"] + total
    if score > STATS["best_score"]:
        STATS["best_score"] = score
        STATS["best_total"] = total
    print()
    again = input("Play again? (y/n): ")
    if again != "y":
        save_stats()
        break

print("Thanks for playing!")

Load Stats at Startup

Instructions

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