query[k] = v
if date_range:
query['start_date'] = date_range
+
+ # if $lt is not provided,
+ # empty/None/null/'' start_date will also be returned
+ if 'start_date' in query and '$lt' not in query['start_date']:
+ query['start_date'].update({'$lt': str(datetime.now())})
+
return query