code: public void setSizeSegment(com.google.api.ads.admanager.axis.v201808.CreativePlaceholder[] sizeSegment) {
          this.sizeSegment = sizeSegment;
      }
docs: Sets the sizeSegment value for this ProductSegmentation.
  
  @param sizeSegment   * The creative size segmentation.
  
  <p>This attribute is optional.