Fixed Google Colab link in week 3 day 4, and latest week 8 updates

week8_wip/agents/specialist_agent.py

@@ -0,0 +1,10 @@
+import modal
+
+class SpecialistAgent:
+
+    def __init__(self):
+        Pricer = modal.Cls.lookup("pricer-service", "Pricer")
+        self.pricer = Pricer()
+        
+    def price(self, description: str) -> float:
+        return self.pricer.price.remote(description)