diff --git a/csppfetch/test.py b/csppfetch/test.py
index 0c0eac4836e5d3e7aac0b0ca82d04df7e515e9d6..1c9785249a8dc224ba9dbca0c5b0f66b599c3f41 100755
--- a/csppfetch/test.py
+++ b/csppfetch/test.py
@@ -683,6 +683,10 @@ class DownloaderTests(DTestCase):
 def add_module_doctest(tests, module, context):
     import warnings
     import doctest
+    # We need to suppress ResourceWarnings that unitttest turns on but are
+    # supurious for doctest. Sadly, we can't restore them when done
+    # because the tearDown function is called _before_ some of these
+    # trigger.
     def suppress(module):
         for mod in (module.__name__, 'doctest'):
             warnings.filterwarnings("ignore",