I have a list, like this:

```
list_1 = [1,2,2,3,1,2]

```

I want to create another nested lists like this:

```
[[1,2,2,1,2],[2,2,3,2]]

```

The first nested list is only composed of 1 and 2 because, according to the numerical order, 2 comes after 1 and 1 is must be included. 3 is not in the first nested list because after 1 comes 2 and not 3.

In the second nested list, there is 2 and 3 because 3 comes after 2 and 2 needs to be included. 1 is not there because one doesn't come after 2.

How can I achieve this in Python 3?