fix precommit errors

llama_stack/providers/utils/kvstore/sqlite/sqlite.py

@@ -21,7 +21,7 @@ class SqliteKVStoreImpl(KVStore):
     def __init__(self, config: SqliteKVStoreConfig):
         self.db_path = config.db_path
         self.table_name = "kvstore"
-        self._conn = None
+        self._conn: aiosqlite.Connection | None = None
 
     def __str__(self):
         return f"SqliteKVStoreImpl(db_path={self.db_path}, table_name={self.table_name})"
@@ -57,6 +57,7 @@ class SqliteKVStoreImpl(KVStore):
             self._conn = None
 
     async def set(self, key: str, value: str, expiration: datetime | None = None) -> None:
+        assert self._conn is not None, "Connection not initialized. Call initialize() first."
         await self._conn.execute(
             f"INSERT OR REPLACE INTO {self.table_name} (key, value, expiration) VALUES (?, ?, ?)",
             (key, value, expiration),
@@ -64,7 +65,10 @@ class SqliteKVStoreImpl(KVStore):
         await self._conn.commit()
 
     async def get(self, key: str) -> str | None:
-        async with self._conn.execute(f"SELECT value, expiration FROM {self.table_name} WHERE key = ?", (key,)) as cursor:
+        assert self._conn is not None, "Connection not initialized. Call initialize() first."
+        async with self._conn.execute(
+            f"SELECT value, expiration FROM {self.table_name} WHERE key = ?", (key,)
+        ) as cursor:
             row = await cursor.fetchone()
             if row is None:
                 return None
@@ -75,10 +79,12 @@ class SqliteKVStoreImpl(KVStore):
             return value
 
     async def delete(self, key: str) -> None:
+        assert self._conn is not None, "Connection not initialized. Call initialize() first."
         await self._conn.execute(f"DELETE FROM {self.table_name} WHERE key = ?", (key,))
         await self._conn.commit()
 
     async def values_in_range(self, start_key: str, end_key: str) -> list[str]:
+        assert self._conn is not None, "Connection not initialized. Call initialize() first."
         async with self._conn.execute(
             f"SELECT key, value, expiration FROM {self.table_name} WHERE key >= ? AND key <= ?",
             (start_key, end_key),
@@ -91,6 +97,7 @@ class SqliteKVStoreImpl(KVStore):
 
     async def keys_in_range(self, start_key: str, end_key: str) -> list[str]:
         """Get all keys in the given range."""
+        assert self._conn is not None, "Connection not initialized. Call initialize() first."
         cursor = await self._conn.execute(
             f"SELECT key FROM {self.table_name} WHERE key >= ? AND key <= ?",
             (start_key, end_key),