Add 'pip install asyncio_redis' note
@@ -258,11 +258,17 @@ which may be connected to a different server instance...
Uvicorn includes broadcast functionality, using Redis Pub/Sub.
+First, make sure to install the `asyncio_redis` package:
+
+```shell
+$ pip install asyncio_redis
+```
+
Broadcast functionality is not integrated directly into the server, but is
included as application-level middleware. You can install the broadcast module
by wrapping it around your existing application, like so:
-```
+```python
from uvicorn.broadcast import BroadCastMiddleware
async def my_app(messages, channels):
