实现一个自动生成小学四则运算题目的命令行程序

def parse_arguments():
    parser = argparse.ArgumentParser(description="Generate arithmetic questions and validate answers.")
    parser.add_argument("-n", type=int, help="Number of questions to generate")
    parser.add_argument("-r", type=int, required=True, help="Range of numbers")
    parser.add_argument("-e", type=str, help="Exercise file to validate")
    parser.add_argument("-a", type=str, help="Answer file to validate")
    return parser.parse_args()

def generate_number(max_range):
    if random.random() < 0.5:
        return random.randint(1, max_range - 1)
    else:
        numerator = random.randint(1, max_range - 1)
        denominator = random.randint(1, max_range - 1)
        while numerator >= denominator:
            numerator = random.randint(1, max_range - 1)
            denominator = random.randint(1, max_range - 1)
        return Fraction(numerator, denominator)

def generate_expression(max_range):
    num_count = random.randint(2, 4)
    nums = [generate_number(max_range) for _ in range(num_count)]
    operators = ['+', '-', '*', '/']
    expression = str(nums[0])

    for i, num in enumerate(nums[1:], start=1):
        operator = random.choice(operators)
        if operator == '-' and nums[i-1] < num:
            nums[i-1], num = num, nums[i-1]
        elif operator == '/':
            if nums[i-1] > num:
                nums[i-1], num = num, nums[i-1]
            else:
                continue
        expression += f" {operator} {num}"

    return expression

def generate_question(max_range):
    expression = generate_expression(max_range)
    return f"{expression} "

def generate_questions(num_questions, max_range):
    questions = set()
    while len(questions) < num_questions:
        question = generate_question(max_range)
        questions.add(question)
    return list(questions)

def calculate_answer(expression):
    try:
        answer = sympify(expression)
        float_answer = float(answer.evalf())
        return int(float_answer) if float_answer.is_integer() else float_answer
    except Exception as e:
        print(f"Error calculating answer: {e}")
        return e

def save_questions(questions, filename="Exercises.txt"):
    with open(filename, "w") as file:
        for idx, question in enumerate(questions, 1):
            file.write(f"四则运算题目{idx}\n{question} = \n")

def save_answers(answers, filename="Answers.txt"):
    with open(filename, "w") as file:
        for idx, answer in enumerate(answers, 1):
            file.write(f"{answer}\n")

def validate_answers(exercise_file, answer_file):
    correct = []
    wrong = []
    question_number = 1
    with open(exercise_file, "r") as ex_file, open(answer_file, "r") as ans_file:
        for ex_line, ans_line in zip(ex_file, ans_file):
            exercise = ex_line.strip()
            try:
                answer = Fraction(ans_line.strip())
                calculated_answer = calculate_answer(exercise)
                if calculated_answer is None:
                    raise ValueError(f"calculate_answer returned None for expression '{exercise}'")
                if calculated_answer == answer:
                    correct.append(f"四则运算题目{question_number}")
                else:
                    wrong.append(f"四则运算题目{question_number}")
                question_number += 1
            except ValueError as e:
                print(f"{e} in line: {ans_line.strip()}")
                wrong.append(f"四则运算题目{question_number}")
                question_number += 1
            except Exception as e:
                print(f"Error calculating answer for: {exercise}. Error: {e}")
                wrong.append(f"四则运算题目{question_number}")
                question_number += 1
    return correct, wrong

def save_grades(correct, wrong, filename="Grade.txt"):
    with open(filename, "w") as file:
        correct_ids = [idx.split("题目")[1] for idx in correct]
        wrong_ids = [idx.split("题目")[1] for idx in wrong]
        file.write(f"Correct: {len(correct)} ({', '.join(correct_ids)})\n")
        file.write(f"Wrong: {len(wrong)} ({', '.join(wrong_ids)})\n")

def main():
    args = parse_arguments()
    if args.n:
        max_range = 10 if args.r >= 10 else args.r
        questions = generate_questions(args.n, max_range)
        answers = [calculate_answer(q) for q in questions]
        save_questions(questions, "Exercises.txt")
        save_answers(answers, "Answers.txt")
    if args.e and args.a:
        print(f"Validating answers using exercise file: {args.e}")
        print(f"And answer file: {args.a}")
        correct, wrong = validate_answers(args.e, args.a)
        print(f"Correct answers: {correct}")
        print(f"Wrong answers: {wrong}")
        save_grades(correct, wrong, "Grade.txt")
        print("Grades have been saved.")