uses the scrapy.Request method to collect pages, but nothing is done.
import scrapy
def ret(response):
print("start print")
print(response.body)
url = "https://doc.scrapy.org/en/latest/intro/tutorial.html"
v = scrapy.http.Request(url=url, callback=ret)
print(url, v)
output:
https://doc.scrapy.org/en/latest/intro/tutorial.html
<GET https://doc.scrapy.org/en/latest/intro/tutorial.html>
The method ret
is not executed at all and cannot print out the corresponding content