import urllib.request

url = 'http://3link1/'
username = 'admin'
password = 'admin'

p = urllib.request.HTTPPasswordMgrWithDefaultRealm()
p.add_password(None, url, username, password)

handler = urllib.request.HTTPBasicAuthHandler(p)
opener = urllib.request.build_opener(handler)
urllib.request.install_opener(opener)

page = urllib.request.urlopen(url).read()
page1 = bytes.decode(page)
print(page1)