routine which updates chromedriver-py package on its own

chromedriver-updater.py

# constants
CHROME_DL_URL = 'https://chromedriver.storage.googleapis.com'
CHROME_URL = 'http://chromedriver.chromium.org/downloads'
REPO_PATH = './GitHub/chromedriver-py/'
VERSION_FILE = './GitHub/chromedriver-py/version.txt'
DOWNLOAD_DIR = './'
CURRENT_VERSION = [] 
UPDATE_SCRIPT = './update_chromedriver.sh'

# chromedriver versions for downloading only
DRIVER = 'chromedriver_'
ZIP = '.zip'
vMAC = DRIVER + 'mac64' + ZIP
vWINDOWS = DRIVER + 'win32' + ZIP
vLINUX = DRIVER + 'linux64' + ZIP
PLATFORMS = [ vMAC, vLINUX, vWINDOWS ]

import os

if not CURRENT_VERSION:
    with open(VERSION_FILE) as f:
        file_content = f.read()
        if file_content:
            CURRENT_VERSION = file_content.strip().split('.')
        else:
            CURRENT_VERSION = [0, 0]

print(CURRENT_VERSION)

import requests
from bs4 import BeautifulSoup as bs
import urllib

page = requests.get(CHROME_URL)
html = page.content

soup = bs(html, 'html.parser')

latest = soup.find(id='sites-canvas-main-content').table.tbody.tr.td.div.find_all('h2')[1].b.a

new_version = latest.text.split(' ')[1].split('.')
print(str(new_version))

# update logic
length = len(new_version)
if len(CURRENT_VERSION) < length:
    length = len(CURRENT_VERSION)

update = False
for i in range(length):
    new = int(new_version[i])
    old = int(CURRENT_VERSION[i])

    if new > old:
        update = True
        break

if update:
    for pf in PLATFORMS:
        url = CHROME_DL_URL + '/' + '.'.join(new_version) + '/' + pf
        print(url)

        # downloads the files
        file = urllib.request.urlopen(url)
        path = os.path.join(DOWNLOAD_DIR, pf)

        with open(path,'wb') as output:
            output.write(file.read())

        # unzip file
        import zipfile
        with zipfile.ZipFile(path,"r") as zip_ref:
            zip_ref.extractall(DOWNLOAD_DIR)

        # rename file
        if 'linux' in pf:
            os.rename(os.path.join(DOWNLOAD_DIR, 'chromedriver'), os.path.join(DOWNLOAD_DIR, 'chromedriver_linux'))
        elif 'mac' in pf:
            os.rename(os.path.join(DOWNLOAD_DIR, 'chromedriver'), os.path.join(DOWNLOAD_DIR, 'chromedriver_mac'))

        # delete zip file
        os.remove(path)


    # update version file
    with open(VERSION_FILE, 'w') as vFile:
        vFile.write('.'.join(new_version))

    # start shell script to update package
    import subprocess
    subprocess.call(UPDATE_SCRIPT, shell=True)