code: function(path, options) {
  
          var cell = this.options.cellView.model;
  
          var value = joint.util.getByPath(cell.attributes, path, '/');
          if (_.isUndefined(value) && !_.isUndefined(options.defaultValue)) {
              value = options.defaultValue;
          }
  
          if (options.valueRegExp) {
  
              if (_.isUndefined(value)) {
                  
                  throw new Error('Inspector: defaultValue must be present when valueRegExp is used.');
              }
              
              var valueMatch = value.match(new RegExp(options.valueRegExp));
              value = valueMatch && valueMatch[2];
          }
  
          return value;
      }
docs: Get the value of the attribute at `path` based on the `options.defaultValue`, and `options.valueRegExp` if present.