fixed bug in dist where query_params is None
fixed bug in dist where query_params is None

LearningRegistry/LearningRegistry,jimklo/LearningRegistry,LearningRegistry/LearningRegistry,LearningRegistry/LearningRegistry,LearningRegistry/LearningRegistry,LearningRegistry/LearningRegistry,LearningRegistry/LearningRegistry,jimklo/LearningRegistry,jimklo/LearningRegistry,jimklo/LearningRegistry,jimklo/LearningRegistry,jimklo/LearningRegistry,jimklo/LearningRegistry,LearningRegistry/LearningRegistry,jimklo/LearningRegistry,jimklo/LearningRegistry