see this here
https://sgp1.vultrobjects.com/ETL-Processes/Web-Scraping-Services/web-scraping/4-internet-creeping-versions-web-scratching-with-python.html
The open internet is by far the best global database for human expertise, as well as there is almost no information that you can't locate with extracting web data. Due to the fact that web scraping is done by lots