update docstring

src/py/reactpy/reactpy/core/layout.py

@@ -148,7 +148,9 @@ async def _serial_render(self) -> LayoutUpdateMessage: # nocov
  return await self._create_layout_update(model_state)
 
  async def _parallel_render(self) -> LayoutUpdateMessage:
- """Await the next available render within an asyncio task group."""
+ """Await to fetch the first completed render within our asyncio task group.
+ We use the `asyncio.tasks.wait` API in order to return the first completed task.
+ """
  await self._render_tasks_ready.acquire()
  done, _ = await wait(self._render_tasks, return_when=FIRST_COMPLETED)
  update_task: Task[LayoutUpdateMessage] = done.pop()