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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_current(self):
 """ Returns the current ``UserSettings`` based on the SITE_ID in the project's settings. The ``UserSettings`` object is cached the first time it's retrieved from the database. """

        from django.conf import settings
        try:
            site_id = settings.SITE_ID
        except AttributeError:
            raise ImproperlyConfigured(
                'You\'re using the Django "sites framework" without having '
                'set the SITE_ID setting. Create a site in your database and '
                'set the SITE_ID setting to fix this error.')

        try:
            current_usersettings = USERSETTINGS_CACHE[site_id]
        except KeyError:
            current_usersettings = self.get(site_id=site_id)
            USERSETTINGS_CACHE[site_id] = current_usersettings
        return current_usersettings