diff --git a/tests/test_gpiwriter.py b/tests/test_gpiwriter.py
index 18556109..38cb102e 100644
--- a/tests/test_gpiwriter.py
+++ b/tests/test_gpiwriter.py
@@ -5,6 +5,7 @@
 import pytest
 
 
+@pytest.mark.parametrize("gpad_gpi_output_version", ["2.0", "1.2"])
 @pytest.mark.parametrize("gpad_gpi_output_version", ["2.0", "1.2"])
 def test_produce_gpi(gpad_gpi_output_version):
     # Base path relative to this script
@@ -31,13 +32,13 @@ def test_produce_gpi(gpad_gpi_output_version):
 
     # Verify the contents of the GPI file
     p = entityparser.GpiParser()
-    with output_gpi_path.open() as f:
+    with open(output_gpi_path, "r") as f:
         assert p.parse(f) is not None, "The GPI file could not be parsed."
         f.seek(0)  # Reset file pointer to the beginning
         results = p.parse(f)
         assert len(results) > 5, "The GPI file should have about 9 unique genes from ~ 90 associations in the GAF file."
 
-    with output_gpi_path.open() as f:
+    with open(output_gpi_path, "r") as f:
         lines = f.readlines()
 
     assert len(lines) > 0, "The GPI file should not be empty."