def __init__(self):
        self._comptia = {}
        self._cache = GsxCache("comptia")
Raises ``ValidationError`` if user is already member of given group or
dataset/ETHPy150Open filipp/py-gsxws/gsxws/comptia.py/CompTIA.__init__--crossover with--dataset/ETHPy150Open lukaszb/django-projector/projector/forms.py/DashboardAddMemberForm.clean_user