Silence ResourceWarnings in modulefinder by using file context managers.
diff --git a/Misc/NEWS b/Misc/NEWS
index 795b3d5..b1e701d 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -54,6 +54,8 @@
 Library
 -------
 
+- Close file objects in modulefinder in a timely manner.
+
 - Close a io.TextIOWrapper object in email.parser in a timely manner.
 
 - Close a file object in distutils.sysconfig in a timely manner.