Was this customer flirting?

I work at a supermarket serving customers at checkout. I served a nice blonde girl in gym clothes. And she seemed abit flirty. She had an open smile and a good look in her eye. And also good extended eye contact while still smiling, still looking at me when most people usually don't. I kinda did the same back. I'm not good at describing things sorry, but to me it felt flirty and like she kinda liked me. Was she flirting? May have she liked me?
Was this customer flirting?
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