def __str__(self):
        s = self.alias
        if s is None:
            s = ''
        return s
Split tasks from old apps into 3 categories:
dataset/ETHPy150Open idlesign/django-sitecats/sitecats/toolbox.py/CategoryList.__str__--crossover with--dataset/ETHPy150Open Yelp/paasta/paasta_tools/setup_marathon_job.py/get_old_happy_unhappy_draining_tasks