Add dev stacks

stacks/mllogwatcher/testing.py

@@ -0,0 +1,17 @@
+# pip install -qU langchain "langchain[anthropic]"
+from langchain.agents import create_agent
+
+def get_weather(city: str) -> str:
+    """Get weather for a given city."""
+    return f"It's always sunny in {city}!"
+
+agent = create_agent(
+    model="claude-sonnet-4-5-20250929",
+    tools=[get_weather],
+    system_prompt="You are a helpful assistant",
+)
+
+# Run the agent
+agent.invoke(
+    {"messages": [{"role": "user", "content": "what is the weather in sf"}]}
+)