diff --git a/.travis.yml b/.travis.yml
index dd08915113371f5fabc99c73964f862625ef363f..036c4f9bb389d10f1e98788cfb11772df08e42bc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,6 @@ install:
   - pip install flake8
 
 python:
-  - "2.7"
   - "3.5"
   - "3.6"
 
diff --git a/mmdet/models/single_stage_heads/retina_head.py b/mmdet/models/single_stage_heads/retina_head.py
index cc0492397899d22fba5cd33bf21e691c609665f3..8fd047f99691c06a60823236a338fb97a46c78b7 100644
--- a/mmdet/models/single_stage_heads/retina_head.py
+++ b/mmdet/models/single_stage_heads/retina_head.py
@@ -31,7 +31,7 @@ class RetinaHead(nn.Module):
         anchor_strides (Iterable): Anchor strides.
         target_means (Iterable): Mean values of regression targets.
         target_stds (Iterable): Std values of regression targets.
-    """
+    """  # noqa: W605
 
     def __init__(self,
                  in_channels,