def validate_timeout_or_none(option, value):
    if value is None:
        return value
    return validate_positive_float(option, value) / 1000.0
Create DVR mac address for a given host.
dataset/ETHPy150Open mongodb/mongo-python-driver/pymongo/common.py/validate_timeout_or_none--crossover with--dataset/ETHPy150Open openstack/neutron/neutron/db/dvr_mac_db.py/DVRDbMixin._create_dvr_mac_address