Fix flake8

Author: dpoirier

stack/repository.py

@@ -3,7 +3,6 @@
 from troposphere import (
     AWS_ACCOUNT_ID,
     AWS_REGION,
-    AWS_STACK_NAME,
     Join,
     Output,
     Ref
@@ -20,7 +19,7 @@
     # Do we need to specify a repository name? The stack name might not be
     # a valid repository name, and if we just leave it out, AWS will make one
     # up for us.
-    #RepositoryName=Ref(AWS_STACK_NAME),
+    # RepositoryName=Ref(AWS_STACK_NAME),
     # Allow all account users to manage images.
     RepositoryPolicyText=Policy(
         Version="2008-10-17",