code: def setup(settings):
      
      connector = settings.get('db_connector')
      if connector == 'postgres':
          from playhouse.pool import PooledPostgresqlExtDatabase
          return PooledPostgresqlExtDatabase(settings['db_name'],
                             user=settings['db_user'],
                             password=settings['db_password'],
                             host=settings['db_host'],
                             port=settings.get('db_port'),
                             max_connections=settings.get('db_max_conn'),
                             stale_timeout=settings.get('db_stale_timeout'),
                             timeout=settings.get('db_timeout'),
                             register_hstore=False)
docs: Setup the database connection.