Help find title of this song ? Maybe Sister Sledge
 

Hello everybody, I need some help finding who is the artist and maybe also the title of this funky song (link above). I took it from an italian film called ecce bombo, which unfortunately doesn't have an offical soundtrack, and this song is not even mentioned in the score.
The movie was released in 1978 so the song is older.



It seems like it could be some group like sister sledge maybe ?
If you don't know the song, could you help maybe with the lyrics? It seems somthing like "bang bang bang to the disco" ?

Thanks in advice!

Okay now I've adjusted the link to the video