Update unit2/llama-index/workflows.ipynb

wrong placement of "| LoopEvent". It should be placed in "step_one": step_one(self, ev: StartEvent | LoopEvent), and NOT in "step_two"! The "step_two" should be without the "| LoopEvent": step_two(self, ev: ProcessingEvent). Why can't you even copy the demo code correctly?! The whole code of Chapter 2 is messed up!

unit2/llama-index/workflows.ipynb

@@ -182,7 +182,7 @@
     "\n",
     "class MultiStepWorkflow(Workflow):\n",
     "    @step\n",
-    "    async def step_one(self, ev: StartEvent) -> ProcessingEvent | LoopEvent:\n",
+    "    async def step_one(self, ev: StartEvent | LoopEvent) -> ProcessingEvent | LoopEvent:\n",
     "        if random.randint(0, 1) == 0:\n",
     "            print(\"Bad thing happened\")\n",
     "            return LoopEvent(loop_output=\"Back to step one.\")\n",
@@ -191,7 +191,7 @@
     "            return ProcessingEvent(intermediate_result=\"First step complete.\")\n",
     "\n",
     "    @step\n",
-    "    async def step_two(self, ev: ProcessingEvent | LoopEvent) -> StopEvent:\n",
+    "    async def step_two(self, ev: ProcessingEvent) -> StopEvent:\n",
     "        # Use the intermediate result\n",
     "        final_result = f\"Finished processing: {ev.intermediate_result}\"\n",
     "        return StopEvent(result=final_result)\n",