Well, this is just a Python web scraper, and Instagram does in fact attempt to detect and prevent/rate-limit this kind of scraping. They rely very heavily on the source IP to help them determine when to cut you off.
... indeed. Isn't the script 'under the hood' calling the API anyways (looking at 'scrolldown' here)?
I reversed engineered the API myself a couple of weeks ago which was great fun - especially figuring out Instagram's rate limits on interactions such as comments and likes per day/hr.
