code: function _noShepherdOrSoError(node) {
      if (!node.shepherd)
          return new Error('This node did not register to the mqtt-shepherd.');
      else if (!node._registered)
          return new Error('This node was deregistered.');
      else if (!(node.so instanceof SmartObject))
          return new Error('No smart object bound to this node.');
      else
          return null;
  }
docs: ********************************************************************************************** * Private Functions                                                                         ** **********************************************************************************************