def __virtual__():
    if HAS_JUNOS and 'proxy' in __opts__:
        return __virtualname__
    else:
        return (False, 'The junos module could not be \
                loaded: junos-eznc or proxy could not be loaded.')
We need the Junos adapter libraries for this
dataset/ETHPy150Open saltstack/salt/salt/modules/junos.py/__virtual__