* Shirley Temples are non-alcoholic: They're made with ginger ale and a splash of grenadine. There's no alcohol content.
* Harry Potter is fictional: He's not a real person with a real metabolism and tolerance to alcohol.
* Alcohol tolerance varies greatly: Even if we were talking about a real person, the number of drinks needed to get drunk depends on many factors, including weight, gender, genetics, and even what they've eaten that day.
So, the short answer is: No number of Shirley Temples could ever make Harry Potter drunk, because they are non-alcoholic.
It's important to remember that alcohol is a serious substance, and it's crucial to drink responsibly and within legal limits.