function Chart() {

	        /**
	         * @type {module:zrender/container/Group}
	         * @readOnly
	         */
	        this.group = new Group();

	        /**
	         * @type {string}
	         * @readOnly
	         */
	        this.uid = componentUtil.getUID('viewChart');
	    }
@public
@param {(Function)} fn
@param {number} [delay=0] Unit: ms.
@param {boolean} [debounce=false]
       true: If call interval less than `delay`, only the last call works.
       false: If call interval less than `delay, call works on fixed rate.
@return {(Function)} throttled fn.