diff --git a/corrlib/meas_io.py b/corrlib/meas_io.py
index 1a06dac..fca5671 100644
--- a/corrlib/meas_io.py
+++ b/corrlib/meas_io.py
@@ -6,7 +6,7 @@ from .input import sfcf,openQCD
 import json
 from typing import Union
 from pyerrors import Obs, Corr, dump_object, load_object
-from hashlib import sha256
+from hashlib import sha256, sha1
 from .tools import cached
 import shutil