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How does a for loop work under the hood?

Q: How does a for loop work under the hood?

`for x in obj:` is syntactic sugar for the **iterator protocol**. Python calls `iter(obj)` **once** to get an iterator, then calls `next(it)` **repeatedly**, binding each result to `x`, until `next` raises **`StopIteration`** — which the loop catches silently to stop: iter(obj) __iter__ (once) next(it) __next__ (loop)</te

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iter, next, StopIteration.

iterationfor-loop

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PYManually driving the protocol a for loop hides

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