public function userWeeklyTopArtists(string $username, \DateTime $startdate): Lastfm
    {
        $this->query = array_merge($this->query, [
            'method' => 'user.getWeeklyArtistChart',
            'user' => $username,
            'from' => $startdate->format('U'),
            'to' => $startdate->modify('+7 day')->format('U'),
        ]);

        $this->pluck = 'weeklyartistchart.artist';

        return $this;
    }