code: function(template, cssSelector) {
          self.svgTemplate = template;
          self.svgCssSelector = cssSelector || 'image[xlink:href]';
          if (typeof self.svgTemplate !== 'string') {
            self._injectImage(self.svgTemplate);
          }
        }
docs: SVG(template, cssSelector) define a new SVG template for this node,
  where the cssSelector point either to a DOM Element or a DOM Attribute.
  If the selector points to an element, an image tag will be injected inside ;
  If the selector points to an attribute, the image URL will be injected in that attribute.