Restores a color set instance from the inputed string data.
        
        :param      strdata | <str>

def fromString( cls, strdata ):
        """
        Restores a color set instance from the inputed string data.
        
        :param      strdata | <str>
        """
        if ( not strdata ):
            return None
            
        from xml.etree import ElementTree
        
        xelem = ElementTree.fromstring(str(strdata))
        output = cls(xelem.get('name'), xelem.get('colorGroups').split(','))
        
        for xcolor in xelem:
            colorName = xcolor.get('name')
            
            for xcolorval in xcolor:
                color = QColor( int(xcolorval.get('red')),
                                int(xcolorval.get('green')),
                                int(xcolorval.get('blue')),
                                int(xcolorval.get('alpha')) )
                
                output.setColor(colorName, color, xcolorval.get('group'))
        
        return output