def getlist(self, name, default=None):
        """
        Get a setting value as a list. If the setting original type is a list, a
        copy of it will be returned. If it's a string it will be split by ",".

        For example, settings populated through environment variables set to
        ``'one,two'`` will return a list ['one', 'two'] when using this method.

        :param name: the setting name
        :type name: string

        :param default: the value to return if no setting is found
        :type default: any
        """
        value = self.get(name, default or [])
        if isinstance(value, six.string_types):
            value = value.split(',')
        return list(value)

        Get a setting value as a list. If the setting original type is a list, a
        copy of it will be returned. If it's a string it will be split by ",".

        For example, settings populated through environment variables set to
        ``'one,two'`` will return a list ['one', 'two'] when using this method.

        :param name: the setting name
        :type name: string

        :param default: the value to return if no setting is found
        :type default: any
        
stackoverflow/venv/lib/python3.6/site-packages/scrapy/settings/__init__.py