如何在同一个类中使用来自不同方法的变量而不将其作为参数？

class MyClass:
    def __init__(self):
        self.variable1 = None
        self.variable2 = None

    def method1(self):
        self.variable1 = "Hello"

    def method2(self):
        self.variable2 = "World"

    def method3(self):
        if self.variable1 is not None and self.variable2 is not None:
            print(self.variable1 + " " + self.variable2)

# 创建类的实例
my_object = MyClass()

# 调用方法来设置变量的值
my_object.method1()
my_object.method2()

# 调用方法来使用变量
my_object.method3()