Searches through the modules in self.__crawer_module for a crawler with
        the name passed along.

        :param str crawler: Name of the crawler to load
        :rtype: crawler-class

def get_crawler_class(self, crawler):
        """
        Searches through the modules in self.__crawer_module for a crawler with
        the name passed along.

        :param str crawler: Name of the crawler to load
        :rtype: crawler-class
        """
        settings = Settings()
        settings.set('SPIDER_MODULES', [self.__crawer_module])
        spider_loader = SpiderLoader(settings)
        return spider_loader.load(crawler)