I've been reading about how to handle Google requested URL hereThere is an example from Google : Pretty URL: www.example.com?myquery#!key1=value1&key2=value2Ugly URL: www.example.com?myquery&_escaped_fragment_=key1=value1%26key2=value2As you can see, in the ugly URL there is  %26 characters, as explained by Google that they need to be unescaped by the web server to obtain the original URL:%00..20%23%25..26%2B%7F..FF As in the example, the %26 (ugly URL) represents the & (pretty URL), so in this case, we need to replace %26 with & to get the original URL.How do we know which character is represented by the special characters that Google replaced? 
How to handle URL encoded parameter separators when responding to AJAX crawled _escaped_fragment?
seo;googlebot;ajax