Fixed #12605 -- Removed redundant import of `ImproperlyConfigured`. Thanks, tmcw.

            ## The following is the same as in django.db.backends.sqlite3.base ##

            settings_dict = self.settings_dict

            if not settings_dict['NAME']:

                from django.core.exceptions import ImproperlyConfigured

                raise ImproperlyConfigured("Please fill out the database NAME in the settings module before using the database.")

            kwargs = {

                'database': settings_dict['NAME'],