diff --git a/tools/releasetools/ota_utils.py b/tools/releasetools/ota_utils.py
index fa9516e..63a863e 100644
--- a/tools/releasetools/ota_utils.py
+++ b/tools/releasetools/ota_utils.py
@@ -817,8 +817,8 @@
     target_dir = ExtractTargetFiles(target_file)
     cmd = ["delta_generator",
            "--out_file", payload_file]
-    with open(os.path.join(target_dir, "META", "ab_partitions.txt")) as fp:
-      ab_partitions = fp.read().strip().split("\n")
+    with open(os.path.join(target_dir, "META", "ab_partitions.txt"), "r") as fp:
+      ab_partitions = fp.read().strip().splitlines()
     cmd.extend(["--partition_names", ":".join(ab_partitions)])
     cmd.extend(
         ["--new_partitions", GetPartitionImages(target_dir, ab_partitions, False)])