They've been singing this since the Romans and them were going at each other's throats. Such is their pride in their confections, that they become battle hymns of sugary glory.
So the group is Die Lollipops... feminine gender, that's fine. But the song is Sommer DER Lollipops... masculine? Furthermore it appears they live in a world with two differently gendered suns. die Sonne and der Sonne.