Transform Laravel collection and group by key - php

Question

I would like to transform a collection of object in laravel, but I can't figure it out how. I want to group the record by the type column, and set the grouped record under an array key value.
public function transformData()
{
$data = collect();
$matches = [ 'race', 'ethnicity'];
$attributes = Attribute::withTrashed()
->whereIn('type', $matches)
->get()
->groupBy('type');
$data->put(
$type, // to be the group key(like race)
[
'values' => $attributes->toArray(), // to be all the value with type race
]
);
dd(collect($data));
}
Here is what I'm getting:
Illuminate\Support\Collection^ {#2368
#items: array:1 [
"values" => array:2 [
"ethnicity" => array:2 [
0 => array:2 [
"id" => 1
"type" => "ethnicity"
]
1 => array:2 [
"id" => 2
"type" => "ethnicity"
]
]
"race" => array:2 [
0 => array:2 [
"id" => 6
"type" => "race"
]
1 => array:2 [
"id" => 7
"type" => "race"
]
]
]
]
#escapeWhenCastingToString: false
}
BUT I would like to return this instead:
Illuminate\Support\Collection^ {#2368
#items: array:1 [
"ethnicity" => array:2 [
"value" => array:2 [
0 => array:2 [
"id" => 1
"type" => "ethnicity"
]
1 => array:2 [
"id" => 2
"type" => "ethnicity"
]
]
]
"race" => array:2 [
"value" =>
0 => array:2 [
"id" => 6
"type" => "race"
]
1 => array:2 [
"id" => 7
"type" => "race"
]
]
]
#escapeWhenCastingToString: false
}