- It provides a unified style to express graph and kernel for user.
- It provides a unified IR to represent graph and kernel for developer.
- It breaks the boundary between graph and kernel.
- It provides more opportunities to do compile optimization.

format code

remove save_graph

raise exception when dictionary setitem if the key not exists

resolve error

remove unnessary op_

Signed-off-by: leonwanghui <leon.wanghui@huawei.com>