Well, the mistake here is that someone forgot to pluralize "the raspberries" to "les framboises."

Clearly the real title of the tune is "The Strawberries and The Raspberries," but it scans better in English with the title that Will Holt chose.

First year French students might be tempted to translate the "nous avons bus" as "we have drunk," ("nous"=we "avons"=have "bus"=drunk) but mais non! The basic past tense in French is called the passé composé, and it always includes part of the verb "to have" - but that part is never translated . Context determines whether we understand a phrase as our own simple past ("we drank") or our present perfect ("we have drunk").