Is there any difference between `np.matmul()` and `@`?

Hi all,
I searched some documents of numpy, it said that np.matmul() and @ are same. However, for the assignment of week1, it is an error if I use @, while everything goes well if I use np.matmul(). I am really confused about it. (That is when I use @, all the unit tests passed, but it stuck when I run the following code blocks)

Thanks very much!

Frank

Hi Frank, I will send you a direct message.