diff --git a/micromagnetictests/calculatortests/info_file.py b/micromagnetictests/calculatortests/info_file.py
index 2e71e1d..85e3a8f 100644
--- a/micromagnetictests/calculatortests/info_file.py
+++ b/micromagnetictests/calculatortests/info_file.py
@@ -41,8 +41,8 @@ def test_info_file(calculator):
     assert "driver" in info
 
     assert info["drive_number"] == 0
-    assert re.findall(r"\d{4}-\d{2}-\d{2}", info["date"]) is not []
-    assert re.findall(r"\d{2}:\d{2}-\d{2}", info["time"]) is not []
+    assert re.findall(r"\d{4}-\d{2}-\d{2}", info["date"]) != []
+    assert re.findall(r"\d{2}:\d{2}-\d{2}", info["time"]) != []
     assert info["driver"] == "TimeDriver"
     assert info["t"] == 25e-12
     assert info["n"] == 10
@@ -64,8 +64,8 @@ def test_info_file(calculator):
     assert "driver" in info
 
     assert info["drive_number"] == 1
-    assert re.findall(r"\d{4}-\d{2}-\d{2}", info["date"]) is not []
-    assert re.findall(r"\d{2}:\d{2}-\d{2}", info["time"]) is not []
+    assert re.findall(r"\d{4}-\d{2}-\d{2}", info["date"]) != []
+    assert re.findall(r"\d{2}:\d{2}-\d{2}", info["time"]) != []
     assert info["driver"] == "MinDriver"
 
     calculator.delete(system)