ng count of 1 and a weak
count of 0. In the inner scope, we create `branch` and associate it with
`leaf`, at which point when we print the counts, the `Rc<Node>` in `branch`
will have a strong count of 1 and a weak count of 1 (for `leaf.parent` pointing
to `branch` with a `Weak<Node>`). When we print the counts in `leaf`, we’ll see
it will have a strong count of 2, because `branch` now has a clone of the
`Rc<Node>` of `leaf` stored in `branch.children`, but will still have a weak
count of 0.
-->
<p><code>