### Seeking an efficient filter for partitions.

From the docs:

```
sage: Partitions(4, max_part=2).list()
[[2, 2], [2, 1, 1], [1, 1, 1, 1]]
```

I find this parlance confusing. ~~Obviously the
~~Obviously
the partition [1, 1, 1, 1] has no max part = 2. Be that as it may, I do want to filter those
partitions which greatest part is 2, so in the
example would return

```
[[2, 2], [2, 1, 1]].
```

What is the most efficient way to implement

```
P(n,k) = Partitions(n, MAX_PART=k)
```

where MAX_PART is defined in my sense?