def __sub__(self, other):
        if not isinstance(other, Counter):
            return NotImplemented
        result = Counter()
        for elem in set(self) | set(other):
            newcount = self[elem] - other[elem]
            if newcount > 0:
                result[elem] = newcount
        return result
Validate the options passed at the command line.
dataset/ETHPy150Open PythonCharmers/python-future/docs/3rd-party-py3k-compat-code/pandas_py3k.py/_Counter.__sub__--crossover with--dataset/ETHPy150Open dimagi/commcare-hq/hqscripts/generic_queue.py/GenericEnqueuingOperation.validate_args