html - python requests & beautifulsoup bot detection

Question

I'm trying to scrape all the HTML elements of a page using requests & beautifulsoup. I'm using ASIN (Amazon Standard Identification Number) to get the product details of a page. My code is as follows:

from urllib.request import urlopen
import requests
from bs4 import BeautifulSoup

url = "http://www.amazon.com/dp/" + 'B004CNH98C'
response = urlopen(url)
soup = BeautifulSoup(response, "html.parser")
print(soup)

But the output doesn't show the entire HTML of the page, so I can't do my further work with product details. Any help on this?

EDIT 1:

From the given answer, It shows the markup of the bot detection page. I researched a bit & found two ways to breach it :

1. I might need to add a header in the requests, but I couldn't understand what should be the value of header.
2. Use Selenium. Now my question is, do both of the ways provide equal support?

Answer 1

It is better to use fake_useragent here for making things easy. A random user agent sends request via real world browser usage statistic. If you don't need dynamic content, you're almost always better off just requesting the page content over HTTP and parsing it programmatically.

import requests
from fake_useragent import UserAgent
headers = {'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36'}
ua=UserAgent()
hdr = {'User-Agent': ua.random,
      'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
      'Accept-Charset': 'ISO-8859-1,utf-8;q=0.7,*;q=0.3',
      'Accept-Encoding': 'none',
      'Accept-Language': 'en-US,en;q=0.8',
      'Connection': 'keep-alive'}
url = "http://www.amazon.com/dp/" + 'B004CNH98C'
response = requests.get(url, headers=hdr)
print response.content

Selenium is used for browser automation and high level web scraping for dynamic contents.