need to be more careful in re escaping because Python 3.6

zc.recipe.egg_/src/zc/recipe/egg/tests.py

@@ -89,7 +89,7 @@ def test_suite():
                 (re.compile("(d  ((ext)?demo(needed)?|other)"
                             "-\d[.]\d-py)\d[.]\d(-\S+)?[.]egg"),
                  '\\1V.V.egg'),
-                (re.compile('extdemo.c\n.+\\extdemo.exp\n'), ''),
+                (re.compile('extdemo.c\n.+\\\\extdemo.exp\n'), ''),
                 (re.compile(
                     r'zip_safe flag not set; analyzing archive contents.*\n'),
                  ''),