How avoid Scrapy garbage in response : Hi and thanks in advance:

When I run scrapy I put the items in a .json but furthermore the items I want I get some garbage:

[download latency,download tieout, depth and download slot are the not desired ones][1]


     1 import scrapy
     2
     3 class LibresSpider(scrapy.Spider):
     4     name = 'libres'
     5     allowed_domains = ['www.todostuslibros.com']
     6     start_urls = ['https://www.todostuslibros.com/mas_vendidos/']
     7
     8     def parse(self, response):
     9         for tfg in response.css('li.row-fluid'):
    10             doc={}
    11             data = tfg.css('book-basics')
    12             doc['titulo'] = tfg.css('h2 a::text').extract_first()
    13             doc['url'] = response.urljoin(tfg.css('h2 a::attr(href)').extract_first())
    14
    15             yield scrapy.Request(doc['url'], callback=self.parse_detail, meta=doc)
    16
    17         next = response.css('a.next::attr(href)').extract_first()
    18         if next is not None:
    19            next_page = response.urljoin(next)
    20            yield scrapy.Request(next_page, callback=self.parse)
    21
    22     def parse_detail(self, response):
    23
    24         detail = response.meta
    25         detail['page_count'] = ' '.join(response.css('dd.page.count::text').extract())
    26         detail['keywords'] = ' '.join(response.css('div.descripcio a::text').extract())
    27
    28         yield detail

I  know that those undesired data came whith the response (line 26) but I would to know how avoid that data ends in my json.


  [1]: https://i.stack.imgur.com/iAJdO.png