def get_memory_usage():
    meminfo = parse_meminfo()
    total = meminfo.get('memtotal', 0)
    free = meminfo.get('memfree', 0)
    free += meminfo.get('cached', 0)
    free += meminfo.get('buffers', 0)
    return {
        'total': total,
        'free': free,
        'used': free - total
    }
dataset/ETHPy150Open docker/openstack-docker/nova-driver/hostinfo.py/get_memory_usage/swapped operands of `-`