Scraping Data from AJAX Based Website in Python

from lxml import html
import requests
import re
import mysql.connector

cnx = mysql.connector.connect(user='root', password='',
                              host='127.0.0.1',
                              database='python_db')

page = ""
with open('C://scraping/page.txt', 'r') as myfile:
  page = myfile.read()
tree = html.fromstring(page)

page = requests.get('http://localhost/scraping/page.php')
tree = html.fromstring(page.content)

productName = tree.xpath('//li[class=""="product"]//a[@href]//div[class=""="pro-con"]//h3/text()')
#productBrand = tree.xpath('//ul[class=""="products-grid"]//h2[class=""="product-name"]//div[class=""="cstm_brnd"]//span[1]/text()')
#oldPrices = tree.xpath('//ul[class=""="products-grid"]//p[class=""="old-price"]//span[class=""="price"]/text()')
newPrices = tree.xpath('//li[class=""="product"]//a[@href]//div[class=""="pro-con"]//h4/text()')
#discount = tree.xpath('//ul[class=""="products-grid"]//span[class=""="discount_Span"]/text()')
imagePath = tree.xpath('//li[class=""="product"]//a[@href]//img[class=""="lazz"]//@data-src')
#imagePath = tree.xpath('//img/@data-src')

limit = 0;
for arrayRange in productName:
    limit = limit + 1

def index_exists(ls, i):
    return (0 <= i < len(ls)) or (-len(ls) <= i < 0)

pName = "";
pBrand = "";
pOldPrices = "";
pNewPrices = "";
pDiscount = "";
pImagePath = "";

cursor = cnx.cursor()
for indexNumber in range(limit):
    if index_exists(productName, indexNumber):
        pName = productName[indexNumber]
    else:
        pName = "NA"
    if index_exists(productBrand, indexNumber):
        pBrand = productBrand[indexNumber];
    else:
        pBrand = "NA"
    if index_exists(oldPrices, indexNumber):
        pOldPrices = re.sub('\s+','',oldPrices[indexNumber])
    else:
        pOldPrices = "NA"
    if index_exists(newPrices, indexNumber):
         pNewPrices = re.sub('\s+','',newPrices[indexNumber])
    else:
        pNewPrices = "NA"
    if index_exists(discount, indexNumber):
        pDiscount = discount[indexNumber]
    else:
        pDiscount = "NA"
    if index_exists(imagePath, indexNumber):
        pImagePath = imagePath[indexNumber]
    else:
        pImagePath = "NA"
    cursor.execute("INSERT INTO data(product_name, product_brand, old_price, new_price, discount, image_path)VALUES"
                   "('"+pName+"','"+pBrand+"','"+pOldPrices+"','"+pNewPrices+"','"+pDiscount+"','"+pImagePath+"')")
cnx.close()

totalProducts = 0;
for indexNumber in range(limit):
    print(productName[indexNumber])
    print(newPrices[indexNumber])
    print(imagePath[indexNumber] +"\n")
    totalProducts = totalProducts + 1;

print("Total Products is: ", totalProducts)
print("--------All Products are saved in MySQL Database--------")