Example:

class AbstractMap( JSClass ):
    def __init__( self, name, engine=None ):
        JSClass.__init__( self, engine , self.__class__.__name__ )
        self.map = None
        self.points = {}

     def showPoints( self, points ):
        for point in points:
            self.addPoint( point )

     def getCenter( self ,points=None):
        """ Justify ( Zoom ) map to view all markers """
        if points==None:
            points = self.points
        (maxlat,minlat,maxlng,minlng )= self.getBound( points )
        return ( (minlat + (maxlat-minlat)/2.0),minlng + ( maxlng-minlng)/2 )