update.py

import sys
import os
import time

py = sys.version_info
if py < (3, 0, 0):
    input = raw_input

_version = 1.0


def check_update():
    if _version == 1.0:
        return True
    return False


def update():
    """
        your update code
    """
    with open(os.path.abspath(os.path.basename(__file__)), 'r+') as f:
        buffer = f.read()
        buffer = buffer.replace('_version = 1.0', '_version = 2.0')
        f.seek(0, 0)
        f.write(buffer)


if __name__ == '__main__':
    print('version: ' + str(_version))
    print('now it is running')
    time.sleep(2)
    if check_update():
        choice = input(
            'Now there is a new version, Do you want to update ?')
        if choice in ('y', 'Y'):
            update()
            os.execvp(sys.executable, [sys.executable] + sys.argv)