Sets the pen for this node.
        
        :param      color     <QColor> || None

def setPenColor(self, color):
        """
        Sets the pen for this node.
        
        :param      color     <QColor> || None
        """
        color = QColor(color)
        if self._palette is None:
            self._palette = XNodePalette(self._scenePalette)
        
        self._palette.setColor(self._palette.NodeForeground, color)
        self.setDirty()