Execute an unmodified puppet_node_classifier and read the output as YAML

def ext_pillar(minion_id,
               pillar,  # pylint: disable=W0613
               command):
    '''
    Execute an unmodified puppet_node_classifier and read the output as YAML
    '''
    try:
        data = salt.utils.yaml.safe_load(__salt__['cmd.run']('{0} {1}'.format(command, minion_id)))
        return data['parameters']
    except Exception:
        log.critical('YAML data from %s failed to parse', command)
        return {}