PR: https://github.com/apache/incubator-mxnet/pull/15210

How Custom Operators Work

MXNet allows users to create custom operators if the existing NDArray operators cannot meet their needs. However, profiling operator is not well supported currently.

...

Below is the new visualization after my change:

This is to be compared with the old visualization:

The two screenshot are produced with the same *code*:

```
import mxnet as mx
from mxnet import nd
from mxnet import profiler
from mxnet import context
import threading

...