diff --git a/google/auth/jwt.py b/google/auth/jwt.py
index 394a7d5..12c95eb 100644
--- a/google/auth/jwt.py
+++ b/google/auth/jwt.py
@@ -48,9 +48,9 @@
 
 from six.moves import urllib
 
+from google.auth import _helpers
 from google.auth import credentials
 from google.auth import crypt
-from google.auth import _helpers
 
 
 _DEFAULT_TOKEN_LIFETIME_SECS = 3600  # 1 hour in sections