`PyRegionIterator` did not account for start index/step, so this commit removes it in favor of the sequence iterator provided by CPython. The previous attempt in #137232 bitrotted, so I decided to open a new PR.
`PyRegionIterator` did not account for start index/step, so this commit removes it in favor of the sequence iterator provided by CPython. The previous attempt in #137232 bitrotted, so I decided to open a new PR.