diff --git a/specs/lightclient/sync-protocol.md b/specs/lightclient/sync-protocol.md
index ff9231365..aaff7c580 100644
--- a/specs/lightclient/sync-protocol.md
+++ b/specs/lightclient/sync-protocol.md
@@ -133,7 +133,7 @@ def validate_update(memory: LightClientMemory, update: LightClientUpdate) -> boo
 
 #### `update_memory`
 
-```
+```python
 def update_memory(memory: LightClientMemory, update: LightClientUpdate) -> None:
     memory.header = update.header
     epoch = compute_epoch_at_slot(update.header.slot)