### Easiest way to work in the multiplicative group of Zmod(n)

Given an integer $n$, one can define in SageMath the additive group $\mathbb Z/n\mathbb Z$ by

```
sage: Zn = Zmod(n) # or Integers(n)
```

Now, I would like to work in the multiplicative group $(\mathbb Z/n\mathbb Z)^*$. Of course, I can write

```
sage: G = [a for a in Zn if gcd(a,n) == 1]
sage: Zn(4).multiplicative_order()
6
```

What I would like is an easier way of writing such a thing, such as:

`sage: G = Zn.multiplicative_group() `~~#does ~~# does not exist!
sage: G(4).order()
6

~~And then, I could for instance write ~~Does there exist something ~~like:~~in SageMath to perform such kind of computations?