建立一个分数类fraction，用于表示最简分数

好的，以下是一个简单的分数类Fraction的实现，可以表示最简分数：

class Fraction:
    def __init__(self, numerator, denominator):
        self.numerator = numerator
        self.denominator = denominator
        self.reduce()

    def reduce(self):
        # 求最大公因数
        def gcd(a, b):
            if b == 0:
                return a
            return gcd(b, a % b)

        # 化简分数
        if self.denominator == 0:
            raise ZeroDivisionError("denominator cannot be zero")
        if self.numerator == 0:
            self.denominator = 1
        else:
            common = gcd(self.numerator, self.denominator)
            self.numerator //= common
            self.denominator //= common

    def __str__(self):
        if self.denominator == 1:
            return str(self.numerator)
        return f"{self.numerator}/{self.denominator}"

    def __add__(self, other):
        if isinstance(other, Fraction):
            numerator = self.numerator * other.denominator + self.denominator * other.numerator
            denominator = self.denominator * other.denominator
            return Fraction(numerator, denominator)
        else:
            raise TypeError("unsupported operand type(s) for +: 'Fraction' and '{type(other).__name__}'")

    def __sub__(self, other):
        if isinstance(other, Fraction):
            numerator = self.numerator * other.denominator - self.denominator * other.numerator
            denominator = self.denominator * other.denominator
            return Fraction(numerator, denominator)
        else:
            raise TypeError("unsupported operand type(s) for -: 'Fraction' and '{type(other).__name__}'")

    def __mul__(self, other):
        if isinstance(other, Fraction):
            numerator = self.numerator * other.numerator
            denominator = self.denominator * other.denominator
            return Fraction(numerator, denominator)
        else:
            raise TypeError("unsupported operand type(s) for *: 'Fraction' and '{type(other).__name__}'")

    def __truediv__(self, other):
        if isinstance(other, Fraction):
            numerator = self.numerator * other.denominator
            denominator = self.denominator * other.numerator
            return Fraction(numerator, denominator)
        else:
            raise TypeError("unsupported operand type(s) for /: 'Fraction' and '{type(other).__name__}'")

这个类包含了分数的四则运算，其中使用了递归求最大公因数的方法对分数进行化简。可以通过以下方式使用：

# 创建分数对象
f1 = Fraction(2, 6)
f2 = Fraction(3, 4)

# 打印分数
print(f1)  # 1/3
print(f2)  # 3/4

# 分数加法
print(f1 + f2)  # 17/12

# 分数减法
print(f1 - f2)  # -5/12

# 分数乘法
print(f1 * f2)  # 1/2

# 分数除法
print(f1 / f2)  # 2/9