diff --git a/examples/mlock.py b/examples/mlock.py
index 2ee30ec..e0801b6 100644
--- a/examples/mlock.py
+++ b/examples/mlock.py
@@ -68,7 +68,7 @@ def setup_memory_limit():
         zeroize1(arr)
         zeroize1(arr_np)
         zeroize1(array_array)
-        assert arr = bytearray(int(size * 1024 * 1024))
+        assert arr == bytearray(int(size * 1024 * 1024))
         assert all(arr_np == 0)
         assert all(byte == 0 for byte in array_array)