Remove unused code
Remove unused code

The exception is never raised because the dict lookup uses
default values, thus it is not used at all.

sunhongtao/django-swiftbrowser,hbhdytf/django-swiftbrowser,honza801/django-swiftbrowser,cschwede/django-swiftbrowser,sunhongtao/django-swiftbrowser,honza801/django-swiftbrowser,honza801/django-swiftbrowser,hbhdytf/django-swiftbrowser,cschwede/django-swiftbrowser