Pythonのバージョン上げた後にvirtualenv更新するやつ（Python3.5以上で動作）

update_venv.py

import os
import subprocess

IGNORE = ['i', 'dont','wanna','update', 'these']
VENVS_DIR = os.path.join(os.path.expanduser('~'), '.virtualenvs')


def get_venvs():
    p = subprocess.run("source $(which virtualenvwrapper.sh) && lsvirtualenv -b",
                       shell=True, stdout=subprocess.PIPE)
    return [v.decode('utf8') for v in p.stdout.rstrip().split(b'\n')]


def find_broken_pythons(venvs):
    broken_pythons = {}
    for venv in venvs:
        if venv in IGNORE:
            continue

        venv_dir = os.path.join(VENVS_DIR, venv)
        venv_python = os.path.join(venv_dir, 'bin/python')
        try:
            subprocess.run([venv_python, '-V'], stdout=subprocess.DEVNULL, check=True)
        except subprocess.CalledProcessError:
            broken_pythons[venv] = venv_dir
    return broken_pythons


def remove_broken_symlinks(broken_pythons):
    for venv, venv_dir in broken_pythons.items():
        for root, dirs, files in os.walk(venv_dir):
            for f in files:
                path = os.path.join(root, f)
                if os.path.islink(path) and not os.path.exists(os.readlink(path)):
                    os.unlink(path)


def create_virtualenvs(broken_pythons):
    for venv, venv_dir in broken_pythons.items():
        bin_dir = os.path.join(venv_dir, 'bin')
        python2 = False
        for root, dirs, files in os.walk(bin_dir):
            if 'python2' in files:
                python2 = True
        if python2:
            subprocess.call('virtualenv {}'.format(venv_dir), shell=True)
        else:
            subprocess.call('virtualenv {} -p python3'.format(venv_dir), shell=True)

if __name__ == '__main__':
    venvs = get_venvs()
    broken_pythons = find_broken_pythons(venvs)
    remove_broken_symlinks(broken_pythons)
    # TODO: Link again the unlinked object in case of error
    create_virtualenvs(broken_pythons)