[1.7.x] Removed an unused import

from django.core.management.color import no_style

from django.core.management.sql import (sql_create, sql_delete, sql_indexes,

                                        sql_destroy_indexes, sql_all)

from django.db import connections, DEFAULT_DB_ALIAS, router

from django.db import connections, DEFAULT_DB_ALIAS

from django.test import TestCase