def __call__(self, item):
        self.result[item] += 1
        self.total += 1
Validates value and throws ValidationError. Subclasses should override
dataset/ETHPy150Open mikeorr/WebHelpers2/webhelpers2/containers.py/Counter.__call__--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.2/django/db/models/fields/__init__.py/Field.validate