def __init__(self, profile_directory=None):
        if not FirefoxProfile.DEFAULT_PREFERENCES:
            with open(os.path.join(os.path.dirname(__file__),
                                   WEBDRIVER_PREFERENCES)) as default_prefs:
                FirefoxProfile.DEFAULT_PREFERENCES = json.load(default_prefs)

        self.default_preferences = copy.deepcopy(
            FirefoxProfile.DEFAULT_PREFERENCES['mutable'])
        self.native_events_enabled = True
        self.profile_dir = profile_directory
        self.tempfolder = None
        if self.profile_dir is None:
            self.profile_dir = self._create_tempfolder()
        else:
            self.tempfolder = tempfile.mkdtemp()
            newprof = os.path.join(self.tempfolder, "webdriver-py-profilecopy")
            shutil.copytree(self.profile_dir, newprof,
                            ignore=shutil.ignore_patterns("parent.lock", "lock", ".parentlock"))
            self.profile_dir = newprof
            self._read_existing_userjs(os.path.join(self.profile_dir, "user.js"))
        self.extensionsDir = os.path.join(self.profile_dir, "extensions")
        self.userPrefs = os.path.join(self.profile_dir, "user.js")

    #Public Methods
Manually overwrite the superclass method.
dataset/ETHPy150Open apiad/sublime-browser-integration/selenium/webdriver/firefox/firefox_profile.py/FirefoxProfile.__init__--crossover with--dataset/ETHPy150Open oppia/oppia/core/storage/file/gae_models.py/FileModel._compute_snapshot