def METHOD_NAME(op2: OP2, obj: Any, flag:str,
                           data: bytes, nnodes: int, ntotal: int) -> int:
    n = 0
    dt = np.nan
    fmt = mapfmt(op2._endian + b'2i6f', op2.size)
    s = Struct(fmt)
    for unused_inode in range(nnodes):
        out = s.unpack(data[n:n+ntotal])
        (eid_device, grid_type, tx, ty, tz, rx, ry, rz) = out
        #print(out)
        eid = eid_device // 10
        if op2.is_debug_file:
            op2.binary_debug.write('  %s=%i; %s\n' % (flag, eid, str(out)))
        obj.add_sort1(dt, eid, grid_type, tx, ty, tz, rx, ry, rz)
        n += ntotal
    return n