Python's multi-threaded crawler crawling web page image sample code

import 

# ------ masquerading as a browser ---
def makeOpener(head={
  'Connection': 'Keep-Alive',
  'Accept': 'text/html, application/xhtml+xml, */*',
  'Accept-Language': 'zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2',
  'Connection': 'keep-alive',
  'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:57.0) Gecko/20100101 Firefox/57.0'
  }):
  cj = ()
  opener = .build_opener((cj))
  header = []
  for key, value in ():
    elem = (key, value)
    (elem)
   = header
  return opener

# ------ Getting the source code of a web page ---
# url web link address
def getHtml(url):
  print('url='+url)
  oper = makeOpener()
  if oper is not None:
    page = (url)
    #print ('-----oper----')
  else:
    req=(url)
    # Crawler masquerading as a browser
    req.add_header('User-Agent','Mozilla/5.0 (Windows NT 6.1; WOW64; rv:57.0) Gecko/20100101 Firefox/57.0')
    page = (req)
  html = ()
  if collectHtmlEnabled: #Whether to capture html
    with open('', 'wb') as f:
      (html) # Capture local files to analyze
  # ------ Change the character encoding within the html object to UTF-8 ------
  if chardetSupport:
    cdt = (html)
    charset = cdt['encoding'] #Content analysis with chardet
  else:
    charset = 'utf8'
  try:
    result = (charset)
  except:
    result = ('gbk')
  return result

# ------ Download images based on image url ------
# folderPath Defines the directory where the image is stored imgUrl The address of the link to an image index The index, which indicates the first image.
def downloadImg(folderPath, imgUrl, index):
  # ------ Exception Handling ------
  try:
    imgContent = ((imgUrl)).read()
  except  as e:
    if printLogEnabled : print ('[Error] Current image cannot be downloaded')
    return False
  except  as e:
    if printLogEnabled : print ('[Error] Current image download exception')
    return False
  else:
    imgeNameFromUrl = (imgUrl)
    if printLogEnabled : print ('Downloading section'+str(index+1)+'A picture, picture address:'+str(imgUrl))
    # ------ IO Processing ------
    isExists=(folderPath)
    if not isExists: # directory does not exist, then create
       ( folderPath )
       #print ('Creating directory')
    # Image name naming rules, random strings
    imgName = imgeNameFromUrl
    if len(imgeNameFromUrl) < 8:
      imgName = random_str(4) + random_str(1,'123456789') + random_str(2,'0123456789')+"_" + imgeNameFromUrl
    filename= folderPath + "\\"+str(imgName)+".jpg"
    try:
       with open(filename, 'wb') as f:
         (imgContent) # Write to local disk
       # if printLogEnabled : print ('Downloading of the first '+str(index+1)+'image' completed')
    except :
      return False
    return True

# ------ Batch Download Images ------
# folderPath Defines the directory where images are stored imgList Links to multiple images
def downloadImgList(folderPath, imgList):
  index = 0
  # print ('poolSupport='+str(poolSupport))
  if not poolSupport:
   #print ('Multi-threaded mode')
   # ------ Multithreaded Programming ------
   threads = []
   for imgUrl in imgList:
     # if printLogEnabled : print ('Ready to download the first '+str(index+1)+'image')
     ((target=downloadImg,args=(folderPath,imgUrl,index,)))
     index += 1
   for t in threads:
     (True)
     ()
   () # Parent thread, wait for all threads to end
   if len(imgList) >0 : print ('End of download, directory of stored images:' + str(folderPath))
  else:
   #print ('Thread pooling mode')
    # ------ Thread Pool Programming ------
   futures = []
   # Create a thread pool with a maximum of N tasks thePoolSize global variable
   with (max_workers=thePoolSize) as pool: 
    for imgUrl in imgList:
     # if printLogEnabled : print ('Ready to download the first '+str(index+1)+'image')
     ((downloadImg, folderPath, imgUrl, index))
     index += 1
    result = (futures, timeout=None, return_when='ALL_COMPLETED')
    suc = 0
    for f in :
      if (): suc +=1
    print('End of download, total:'+str(len(imgList))+', number of successes: '+str(suc)+', directory for storing images: ' + str(folderPath))

# ------ Download all images in Baidu posts ------
# folderPath Define the directory where the picture is stored url Baidu Post Link
def downloadImgFromBaidutieba(folderPath='tieba', url='/p/5256331871'):
  html = getHtml(url)
  # ------ Finding an image address using regular expressions to match web content ------
  #reg = r'src="(.*?\.jpg)"'
  reg = r'src="(.*?/sign=.*?\.jpg)"'
  imgre = (reg);
  imgList = (imgre, html)
  print ('Number of images found:' + str(len(imgList)))
  # Download images
  if len(imgList) >0 : downloadImgList(folderPath, imgList) 

# Program entry
if __name__ == '__main__':
  now = ().strftime('%Y-%m-%d %H-%M-%S')
  # Download all images in Baidu posts
  downloadImgFromBaidutieba('tieba\\'+now, '/p/5256331871')