robert@robert-virtual-machine:~/friedrich/didjvu$ git diff -- private/update-coverage
diff --git a/private/update-coverage b/private/update-coverage
index 65f52f9..c02f34e 100755
--- a/private/update-coverage
+++ b/private/update-coverage
@@ -29,7 +29,11 @@ class Coverage(nose.plugins.cover.Coverage):
     stream = None
 
     def report(self, stream):
-        return super(Coverage, self).report(self.stream)
+        robert = super(Coverage, self).report(self.stream)
+        if robert != None:
+            return robert.encode()
+        else:
+            return None
 
 basedir = os.path.join(
     os.path.dirname(__file__),
@@ -49,8 +53,9 @@ def main():
     path = os.path.join('tests', 'coverage')
     plugin = Coverage()
     report_stream = plugin.stream = io.BytesIO()
-    print('Generated automatically by private/update-coverage. '
-        'Do not edit.\n', file=report_stream)
+    #print(b'Generated automatically by private/update-coverage. '
+        #b'Do not edit.\n', file=report_stream)
+    report_stream.write(b'Generated automatically by private/update-coverage. Do not edit.\n')
     ok = nose.run(argv=argv, plugins=[plugin])
     if not ok:
         sys.exit(1)