soup = Bs4(reaponse.text, "lxml")
urls_li = soup.select("#mainmenu_top > div > div > ul > li")

'''
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'''
def get_first_url():
  list_href = []
  reaponse = requests.get("http://www.xxx.com.cn", headers=headers)
  soup = Bs4(reaponse.text, "lxml")
  urls_li = soup.select("#mainmenu_top > div > div > ul > li")
  for url_li in urls_li:
    urls = url_li.select("a")
    for url in urls:
      url_href = url.get("href")
      list_href.append(head_url+url_href)
      out_url = list(set(list_href))
  for reg in out_url:
    print(reg)

def get_next_url(urllist):
  url_list = []
  for url in urllist:
    response = requests.get(url,headers=headers)
    soup = Bs4(response.text,"lxml")
    urls = soup.find_all("a")
    if urls:
      for url2 in urls:
        url2_1 = url2.get("href")
        if url2_1:
          if url2_1[0] == "/":
            url2_1 = head_url + url2_1
            url_list.append(url2_1)
            if url2_1[0:24] == "http://www.xxx.com.cn":
              url2_1 = url2_1
              url_list.append(url2_1)
            else:
              pass
          else:
            pass
        else:
          pass
    else:
      pass
  url_list2 = set(url_list)
  for url_ in url_list2:
    res = requests.get(url_)
    if res.status_code ==200:
      print(url_)
  print(len(url_list2))

get_next_url(url_list2)

import requests
from bs4 import BeautifulSoup as Bs4

head_url = "http://www.xxx.com.cn"
headers = {
  "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.121 Safari/537.36"
}
def get_first_url():
  list_href = []
  reaponse = requests.get(head_url, headers=headers)
  soup = Bs4(reaponse.text, "lxml")
  urls_li = soup.select("#mainmenu_top > div > div > ul > li")
  for url_li in urls_li:
    urls = url_li.select("a")
    for url in urls:
      url_href = url.get("href")
      list_href.append(head_url+url_href)
      out_url = list(set(list_href))
  return out_url


def get_next_url(urllist):
  url_list = []
  for url in urllist:
    response = requests.get(url,headers=headers)
    soup = Bs4(response.text,"lxml")
    urls = soup.find_all("a")
    if urls:
      for url2 in urls:
        url2_1 = url2.get("href")
        if url2_1:
          if url2_1[0] == "/":
            url2_1 = head_url + url2_1
            url_list.append(url2_1)
            if url2_1[0:24] == "http://www.xxx.com.cn":
              url2_1 = url2_1
              url_list.append(url2_1)
            else:
              pass
          else:
            pass
        else:
          pass
    else:
      pass
  url_list2 = set(url_list)
  for url_ in url_list2:
    res = requests.get(url_)
    if res.status_code ==200:
      print(url_)
  print(len(url_list2))
  get_next_url(url_list2)


if __name__ == "__main__":
  urllist = get_first_url()
  get_next_url(urllist)