如何将结构中的联合从c++转换为python？

class Union:
    def __init__(self):
        self.integer = 0
        self.float = 0.0
        self.string = ""

    def set_data(self, data_type, value):
        if data_type == "integer":
            self.integer = value
        elif data_type == "float":
            self.float = value
        elif data_type == "string":
            self.string = value

    def get_data(self):
        if self.integer != 0:
            return ("integer", self.integer)
        elif self.float != 0.0:
            return ("float", self.float)
        elif self.string != "":
            return ("string", self.string)
        else:
            return ("", None)

# 示例用法
union = Union()
union.set_data("integer", 10)
print(union.get_data())  # 输出：('integer', 10)

union.set_data("float", 3.14)
print(union.get_data())  # 输出：('float', 3.14)

union.set_data("string", "Hello")
print(union.get_data())  # 输出：('string', 'Hello')