I'm new in scraping. I've wrote a [scraper](https://github.com/prafulbagai/Scrapper-python) which will scrape [Maplin](http://maplin.co.uk) store. I used Python as the language and BeautifulSoup to scrape the store. 

I want to ask that if I need to scrape some other eCommerce store (say Amazon, Flipkart), do I need to customize my code since they have different HTML schema (`id` and `class` names are different, plus other things as well). So, the scraper I wrote will not work for other eCommerce store.

I want to know how price-comparison sites scrape data from all the online stores? Do they have different code for different online store or is there's a generic one? Do they study the HTML schema of every online store?