Who sings the theme song for the James Bond film "Diamonds Are Forever"?

Sean Connery famously skipped "On Her Majesty's Secret Service," but agreed to return for 1971's "Diamonds Are Forever." He wasn't the only familiar face coming back to the franchise. Shirley Bassey had already knocked "Goldfinger" out of the park in 1964, and the producers wanted that magic again. Now, the exact truth is a little fuzzy here, but one thing is certain: composer John Barry told *someone* to treat the song as a metaphor for a penis. Some sources say the direction was given to lyricist Don Black, which is how we ended up with lines like "They are all I need to please me // They can stimulate and tease me" and "Hold one up and then caress it // Touch it, stroke it and undress it," but some people say Barry put the idea in Bassey's head to get that seductive, sensual feeling for the opening sequence. Quite honestly, my search history can't handle investigating that topic any deeper so you can believe either one. Regardless, the studio liked what it heard and had Barry and Bassey team up again for 1979's "Moonraker."