Python 3爬虫類の解読画像防犯チェーン

import requests, os, os.path, random
from bs4 import BeautifulSoup


def get_soup(url):
    """
         soup  
    """
    req = requests.get(url,)
    html = req.text
    soup = BeautifulSoup(html, features='html.parser')
    return soup


def get_pages(url):
    """
              
    """
    soup = get_soup(url)
    nums = soup.find_all('a', class_='page-numbers')
    pages = int(nums[-2].text)
    return pages


def get_menu(url):
    """
                        ，    
    """
    soup = get_soup(url)
    menu = []
    menu_list = soup.find_all('a', target='_blank')
    for i in menu_list:
        result = i.find_all('img', class_='lazy')
        if result:
            #     
            name = result[0]['alt']
            address = i['href']
            menu.append([name, address])
    return menu


def get_links(url):
    """
                      
    """
    soup = get_soup(url)
    all_ = soup.find_all('a')
    nums = []
    for i in all_:
        span = i.find_all('span')
        if span:
            nums.append(span[0].text)
    return nums[-2]


def get_image(url, filename):
    """
                   filename
    """
    soup = get_soup(url)
    image = soup.find('img').attrs.get('src')

    img_content = requests.get(image,).content
    with open(filename, 'wb') as f:
        f.write(img_content)


def main(page):
    """
       page     
    """
    print('      %s  ' % page)
    page_url = url + '/page/' + str(page)
    menu = get_menu(page_url)
    print('@@@@@@@@@@@@@@@@  %s     %s    @@@@@@@@@@@@@@@@' % (page, len(menu)))
    for i in menu:
        # i[0]        
        dir_name = os.path.join('MeiZiTu', i[0])
        if not os.path.exists(dir_name):
            os.makedirs(dir_name)
        pic_nums = int(get_links(i[1]))
        print('


@@@@@@@@@   %s     %d    @@@@@@@@@
' % (i[0], pic_nums))
        for pic in range(1, pic_nums + 1):
            basename = str(pic) + '.jpg'
            filename = os.path.join(dir_name, basename)
            # MeiZiTu\                   \6.jpg
            pic_url = i[1] + '/' + str(pic)
            #        url  http://www.mzitu.com/102205/3
            if not os.path.exists(filename):
                pass
                print('......%s' % basename, get_image(pic_url, filename))
            else:
                print(filename + '   ，  ')


if __name__ == '__main__':
    url = 'http://www.mzitu.com/'
    pages = get_pages(url)
    print('$$$$$$$$$       %s  $$$$$$$$$$$$$$' % pages)
    if not os.path.exists('MeiZiTu'):
        os.mkdir('MeiZiTu')
    page_start = input('Input the first page number:
')
    page_end = input('Input the last page number:
')
    if int(page_end) > int(page_start):
        for page in range(int(page_start), int(page_end)):
            main(page)
    elif page_end == page_start:
        main(page_end)
    else:
        print("    ，            
")