如何重构切换用例，以便我可以扩展这些用例，并在不同的类中添加另一个用例？

class SwitchCase:
    def execute(self):
        if self.case == 'A':
            self.handle_case_a()
        elif self.case == 'B':
            self.handle_case_b()

    def handle_case_a(self):
        print("Handling case A")

    def handle_case_b(self):
        print("Handling case B")

from abc import ABC, abstractmethod

# 定义策略接口
class SwitchStrategy(ABC):
    @abstractmethod
    def execute(self):
        pass

# 具体策略A
class CaseAStrategy(SwitchStrategy):
    def execute(self):
        print("Handling case A")

# 具体策略B
class CaseBStrategy(SwitchStrategy):
    def execute(self):
        print("Handling case B")

# 上下文类，用于切换策略
class SwitchContext:
    def __init__(self, strategy: SwitchStrategy):
        self._strategy = strategy

    def set_strategy(self, strategy: SwitchStrategy):
        self._strategy = strategy

    def execute_strategy(self):
        self._strategy.execute()

# 使用示例
if __name__ == "__main__":
    context = SwitchContext(CaseAStrategy())
    context.execute_strategy()  # 输出: Handling case A

    context.set_strategy(CaseBStrategy())
    context.execute_strategy()  # 输出: Handling case B