Crawling Reviews of Google Applications

I want to Crawl Website(google App store Reviews) using python 3.5 so i got the answer about using ajax ....

url = "http://ift.tt/1b4RIAf"
param = {'reviewType': '0', 
         'pageNum': '1', 
         'id':'com.venticake.retrica',
         'reviewSortOrder':'4',
         'xhr':'1',
         'token':'ZLqR3TmB64y6koyq8uj1tqqiQ4k:14191636750027',
         'hl':'ko'}

r = requests.post(url, data=param)

d = json.loads(r.text) 

do like this

but response is

')]}\'\n\n[["ecr",1," \\u003cdiv class\\u003d\\"single-review\\" tabindex\\u003d\\"0\\"\\u003e   \\u003cspan\\u003e \\u003cspan

how do i make it to json or structured data ....

thank you for you guys time