diff --git a/snuba/optimize.py b/snuba/optimize.py
index f1d28155b3e..a2af187a95f 100644
--- a/snuba/optimize.py
+++ b/snuba/optimize.py
@@ -1,4 +1,5 @@
 from datetime import timedelta
+from typing import Sequence
 import logging
 
 from snuba import util
@@ -13,7 +14,7 @@ def run_optimize(clickhouse, database, table, before=None):
     return len(parts)
 
 
-def get_partitions_to_optimize(clickhouse, database, table, before=None):
+def get_partitions_to_optimize(clickhouse, database, table, before=None) -> Sequence[util.Part]:
     engine = clickhouse.execute("""
         SELECT engine
         FROM system.tables
@@ -69,7 +70,7 @@ def get_partitions_to_optimize(clickhouse, database, table, before=None):
     parts = [util.decode_part_str(part) for part, count in active_parts]
 
     if before:
-        parts = filter(lambda p: (p[0] + timedelta(days=6 - p[0].weekday())) < before, parts)
+        parts = [p for p in parts if (p[0] + timedelta(days=6 - p[0].weekday())) < before]
 
     return parts
 
diff --git a/snuba/util.py b/snuba/util.py
index 29fc4d15951..a3c6fbb5713 100644
--- a/snuba/util.py
+++ b/snuba/util.py
@@ -9,6 +9,7 @@
 from functools import wraps
 from hashlib import md5
 from itertools import chain, groupby
+from typing import NamedTuple
 import jsonschema
 import logging
 import numbers
@@ -636,7 +637,12 @@ def wrapper(*args, **kwargs):
     return decorator
 
 
-def decode_part_str(part_str):
+class Part(NamedTuple):
+    date: datetime
+    retention_days: int
+
+
+def decode_part_str(part_str: str) -> Part:
     match = PART_RE.match(part_str)
     if not match:
         raise ValueError("Unknown part name/format: " + str(part_str))
@@ -644,7 +650,7 @@ def decode_part_str(part_str):
     date_str, retention_days = match.groups()
     date = datetime.strptime(date_str, '%Y-%m-%d')
 
-    return (date, int(retention_days))
+    return Part(date, int(retention_days))
 
 
 def force_bytes(s):