diff --git a/specs/core/1_new_shards.md b/specs/core/1_new_shards.md
index c27b4d0c9..c3e6ebc53 100644
--- a/specs/core/1_new_shards.md
+++ b/specs/core/1_new_shards.md
@@ -290,7 +290,7 @@ def is_valid_indexed_attestation(state: BeaconState, indexed_attestation: Indexe
 ### `get_attestation_shard`
 
 ```python
-def get_shard(state: BeaconState, attestation: Attestation):
+def get_shard(state: BeaconState, attestation: Attestation) -> Shard:
     return (attestation.data.index + get_start_shard(state, data.slot)) % ACTIVE_SHARDS
 ```