How can I set proxy for the last urllib in Python 3.
I am doing the next
from urllib import request as urlrequest
ask = urlrequest.Request(url)
You should be calling set_proxy() on an instance of class Request, not on the class itself:
from urllib import request as urlrequest
proxy_host = 'localhost:1234' # host and port of your proxy
url = 'http://www.httpbin.org/ip'
req = urlrequest.Request(url)
req.set_proxy(proxy_host, 'http')
response = urlrequest.urlopen(req)
print(response.read().decode('utf8'))