public Site setRetrySleepTime(int retrySleepTime) {
        this.retrySleepTime = retrySleepTime;
        return this;
    }
Set retry sleep times when download fail, 1000 by default. <br>

@param retrySleepTime retrySleepTime
@return this
webmagic-core/src/main/java/us/codecraft/webmagic/Site.java