feat: add py

pub.py

@@ -0,0 +1,35 @@
+class SimplePubSub:
+    def subscribe(self, event, listener):
+        pass
+    def unsubscribe(self, event, listener):
+        pass
+    def publish(self, event, data):
+        pass
+
+# 创建 PubSub 实例
+pubSub = SimplePubSub()
+
+def subscriber1(data):
+    print(f'Subscriber 1 received: {data}')
+
+def subscriber2(data):
+    print(f'Subscriber 2 received: {data}')
+
+# 订阅事件
+pubSub.subscribe('event1', subscriber1)
+pubSub.subscribe('event1', subscriber2)
+
+# 发布事件
+pubSub.publish('event1', 'Hello, World!')
+
+# 取消订阅
+pubSub.unsubscribe('event1', subscriber1)
+
+# 发布事件
+pubSub.publish('event1', 'Hello again!')
+
+# 输出应该是如下的样式
+
+# Subscriber 1 received: Hello, World!
+# Subscriber 2 received: Hello, World!
+# Subscriber 2 received: Hello again!