Who wrote the song "Bang Bang (My Baby Shot Me Down)"?

Stylish colorful retro comic speech bubble on halftone pink color background. Expression text BANG BANG.

mejorana // Shutterstock (Modified by Classic Nerd)

Playing cowboys in the backyard doesn't usually end in heartbreak, but "Bang Bang (My Baby Shot Me Down)" turns those childhood games into a devastating metaphor for getting left by someone you love. Over the years, it's been covered by countless singers. Who wrote the song "Bang Bang (My Baby Shot Me Down)"?