A cop used CPR — which she learned only a week ago — to save a Brooklyn baby yesterday, sources said.

Dad Rostom Omiadze, 39, bolted out of his Bensonhurst yelling for help building when his 1-year-old daughter stopped breathing at 4:45 p.m.

Police arrived, and en route to Lutheran Hospital in a squad car, Officer Atara Ashford, 29, revived the child, who is OK.