How to write a trait function which can be invoked on vec and returns an iterable?

Question

I wrote something which I've been using to combine itertools sort+group.

pub trait SortAndGroup: Iterator {
    fn sort_and_group<K>(self, key_selector: fn(&Self::Item) -> K) -> Vec<(K, Vec<Self::Item>)>
    where
        Self: Sized,
        K: Ord,
    {
        self.sorted_by_key(key_selector)
            .group_by(key_selector)
            .into_iter()
            .map(|(k, g)| (k, g.into_iter().collect::<Vec<_>>()))
            .collect::<Vec<_>>()
    }
}

impl<T: ?Sized> SortAndGroup for T where T: Iterator { }

I usually want to invoke it on some vec and then do some additional mapping and filtering.

Let's say I use it like this:

files
    .iter()
    .sort_and_group(|f| f.joint_folder.clone())
    .into_iter()
    .map(|(joint_folder, g)| {

I'm annoyed that I always have to convert the vec with iter() before calling this and again afterwards call into_iter() on it.

Can I change my trait to have the function callable directly on the Vec and to return something on which I can immediately call map without having to convert the returned value into iterator?

I want to be able to do something like this:

files
    .sort_and_group(|f| f.joint_folder.clone())
    .map(|(joint_folder, g)| {