diff --git a/tests/e2e/fake_llm.py b/tests/e2e/fake_llm.py
index 08dcd665..2be2ce16 100644
--- a/tests/e2e/fake_llm.py
+++ b/tests/e2e/fake_llm.py
@@ -256,6 +256,7 @@ def _plan_complete_step(messages: list[BaseMessage]) -> AIMessage:
 
 
 FOLLOW_UP_REPLY = "Thanks! The PR is ready for review — anything else you'd like changed?"
+_ATTRIBUTION_RE = re.compile(r"@([A-Za-z0-9-]+):")
 
 
 def _latest_attribution(messages: list[BaseMessage]) -> str | None:
@@ -265,6 +266,7 @@ def _latest_attribution(messages: list[BaseMessage]) -> str | None:
             if match:
                 return f"@{match.group(1)}"
     return None
+""
 
 
 def _followup_step(messages: list[BaseMessage]) -> AIMessage: