def prepare_test_settings(self, alias):
        """
        Makes sure the test settings are available in the 'TEST' sub-dictionary.
        """
        try:
            conn = self.databases[alias]
        except __HOLE__:
            raise ConnectionDoesNotExist("The connection %s doesn't exist" % alias)

        test_settings = conn.setdefault('TEST', {})
        for key in ['CHARSET', 'COLLATION', 'NAME', 'MIRROR']:
            test_settings.setdefault(key, None)
dataset/ETHPy150Open django/django/django/db/utils.py/ConnectionHandler.prepare_test_settings