class ProductSpider(scrapy.Spider):
    name = 'product_spider'
allowed_domains = ['ebay.com']
start_urls = [
    'http://www.ebay.com/sch/i.html?_odkw=books&_osacat=0&_trksid=p2045573.m570.l1313.TR0.TRC0.Xpython&_nkw=python&_sacat=0&_from=R40'
    ]

def __init__(self):
    self.driver = webdriver.Firefox()

def parse(self, response):
    pass
selenium with scrapy for dynamic page