Parallel node execution

Parallel node execution Review In module 3, we went in-depth on human-in-the loop, showing 3 common use-cases: (1) Approval - We can interrupt our agent, surface state to a user, and allow the user to accept an action (2) Debugging - We can rewind the graph to reproduce or avoid issues (3) Editing - You can modify the state Goals This module will build on human-in-the-loop as well as the memory concepts discussed in module 2. We will dive into multi-agent workflows and build up to a multi-agent research assistant that ties together all of the modules from this course. To build this multi-agent research assistant, we'll first discuss a few LangGraph controllability topics. We'll start with parallelization. Fan out and fan in Let's build a simple linear graph that over-writes the state at each step.