I am doing a homework, where I need 20 matrices with shape (m,n), with names `a_0`, `a_1`, `a_2`, ..., `a_19`. At first they all can be filled with zeros. How can I do it using for?
Working on `Python`

I can create them all by myself like:

```py
a_0 = np.zeros((m,n))

```

...

```py
a_19 = np.zeros((m,n))

```

but what if I need 1000 matrices?