Here’s a perfect example of the “New York values” that Ted Cruz trashed just to pick a fight with Donald Trump.

An Upper West Side grandmother assumed her $3,000 Chanel bag was gone forever when she accidentally left it behind on a Brooklyn subway bench.

But the 79-year-old woman got the surprise of her life a few hours later — when a cop showed up on her doorstep with the perfectly intact bag, thanks to the honesty of a fellow New Yorker.

“This is the most incredible city in the world!” Fay Mermelstein, a retired jewelry store owner, told The Post on Thursday.

Mermelstein left her bag behind on a bench at the Kings Highway B-train station on Monday after a trip to husband Alex’s back therapist. To her great fortune, it was found by Jean Patrick Baptist, an immigrant from Haiti.

“I thought, what should I do?” Baptist recalled. “I can’t put it in the garbage.”

Baptist, 51, took the next B train from the South Brooklyn station toward his job as a home health aide in Harlem.

He was running late, but still stopped by the 24th Precinct station house on West 100th Street and dropped off the bag.

There, Police Officer Yolanda Cubero, whose family is from Puerto Rico, decided to deliver the tote to Mermelstein’s door.

Mermelstein, who is originally from Ukraine, noted she could always rely on the kindness of her fellow immigrants.

“We are from all over the world,” she said. “There are good people everywhere, and they come to New York, and that’s what makes us incredible.

“We came here with $400 in our hands in 1974,” she said of herself, husband Alex, 80, and their two sons.

When her doorbell rang, “I had just canceled all my credit cards,” Mermelstein recalled. “I saw the officer, and I think, ‘Oh, no! What’s wrong?’ ”

The cop held up Mermelstein’s driver’s license with one hand and kept her other hand behind her back.

“She held up the license, and said, ‘This is yours?’ I said, ‘Yes, where’s the bag?’ She was holding it behind her back!

“I was thinking, ‘I’m going to faint.’ And I was hugging her and saying, ‘Thank you, Officer. Thank you!’ ”

On Wednesday, The Post arranged for the Mermelsteins to also thank Baptist, their good Samaritan.

“Such a sweetheart!” she said of Baptist. “He doesn’t think he did something like a hero. He says, ‘I just did what other people would do.’

“I love New York,” Mermelstein said. “I left Ukraine in 1974, and never, never had a little thing in my heart to say, ‘You have made a mistake.’”

In an attack on Trump Tuesday, Cruz said the billionaire “embodies New York values” — apparently unaware of the compliment he was giving.