Unable to inherit a Qbs item with the same name

I'm trying to create my own Project item which would contain some additional properties. So I write

Project {
    property bool additionalFlag
}

This results in an error:

ERROR: Loop detected when importing '~/Projects/mega/qbs/imports/Project.qbs'.

Okay, fair enough, the item is not smart enough to exclude itself from the lookup and there is a loop indeed. So, I try to break the loop as following:

import qbs as Qbs

Qbs.Project {
    property bool additionalFlag
}

But this produces another error:

ERROR: ~/Projects/mega/qbs/imports/Project.qbs:1:15 Import of qbs.base must have no 'as <Name>'

Expected result:
It should be possible to set a qualified name for any import.

There are other use cases for this too. In the past, I already tried to extend the base Depends item, but had to use another (shitty) name for a new item.