What is the Superman's “stupid line” mentioned in The Less I Know The Better from Tame Impala?

Question

At the end of the song, the lyrics have the following line repeated three times.

Come on superman, say your stupid line.

I think the fact that it is repeated three times is a sign that it is important and not to be overlooked. I don't know what stupid line it is talking about. ¿Does anyone know what it is referring to?

The last part of the song according to lyrics on Google:

Is this what you want, is this who you are?
I was doing fine without ya, 'til I saw your eyes turn away from mine
He's not going where he wants you
Said come on superman, say your stupid line
Said come on superman, say your stupid line
Said come on superman, say your stupid line

Answer 1

It looks like a reference to Superman's line "Up, Up and Away!"

In the song, the narrators ex-girlfriend is sleeping with a new guy Trevor, and our narrator is still seemingly attracted to his ex. However, there is a level of ambiguity with whom Superman actually is. The narrator either perceives Trevor as Superman; thus, wants him gone from this new relationship so he can have another chance with his ex. Or the narrator sees himself as Superman and is trying to remove this whole predicament out of his mind.