diff --git a/python2/typing.py b/python2/typing.py
index 9d24306e..8aae5a2b 100644
--- a/python2/typing.py
+++ b/python2/typing.py
@@ -618,7 +618,7 @@ def _subs_tree(cls, tvars=None, args=None):
     # ... then continue replacing down the origin chain.
     for ocls in orig_chain:
         new_tree_args = []
-        for i, arg in enumerate(ocls.__args__):
+        for arg in ocls.__args__:
             new_tree_args.append(_replace_arg(arg, ocls.__parameters__, tree_args))
         tree_args = new_tree_args
     return tree_args
diff --git a/src/typing.py b/src/typing.py
index bca3a2de..3edb9e2f 100644
--- a/src/typing.py
+++ b/src/typing.py
@@ -563,7 +563,7 @@ def _subs_tree(cls, tvars=None, args=None):
     # ... then continue replacing down the origin chain.
     for ocls in orig_chain:
         new_tree_args = []
-        for i, arg in enumerate(ocls.__args__):
+        for arg in ocls.__args__:
             new_tree_args.append(_replace_arg(arg, ocls.__parameters__, tree_args))
         tree_args = new_tree_args
     return tree_args
diff --git a/tox.ini b/tox.ini
index 42698b3e..2fcbd67b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -13,7 +13,6 @@ changedir = python2
 builtins = basestring, unicode
 ignore =
   # temporary ignores until we sort it out
-  B007,
   E128,
   E129,
   E501,