diff --git a/conftest.py b/conftest.py
index 4931c5a79..05b4ccdad 100644
--- a/conftest.py
+++ b/conftest.py
@@ -21,10 +21,11 @@ collect_ignore = [
     *_py_files("tests/CrawlerRunner"),
 ]
 
-for line in open('tests/ignores.txt'):
-    file_path = line.strip()
-    if file_path and file_path[0] != '#':
-        collect_ignore.append(file_path)
+with open('tests/ignores.txt') as reader:
+    for line in reader:
+        file_path = line.strip()
+        if file_path and file_path[0] != '#':
+            collect_ignore.append(file_path)
 
 if not H2_ENABLED:
     collect_ignore.extend(