@property
    def extensions(self):
        encoded_extensions = []
        for ext in self._extension_files:
            file_ = open(ext, 'rb')
            # Should not use base64.encodestring() which inserts newlines every
            # 76 characters (per RFC 1521).  Chromedriver has to remove those
            # unnecessary newlines before decoding, causing performance hit.
            encoded_extensions.append(base64.b64encode(file_.read()).decode('UTF-8'))

            file_.close()
        return encoded_extensions + self._extensions
alternate: django-admin can't execute user commands unless settings are provided
dataset/ETHPy150Open apiad/sublime-browser-integration/selenium/webdriver/chrome/options.py/Options.extensions--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.2/tests/regressiontests/admin_scripts/tests.py/DjangoAdminAlternateSettings.test_custom_command