class Model(object):
    """docstring for Model."""
    def __init__(self, *args):
        self.var = list(args)

    def added(self, *args):
        self.var = self.var+ list(args)


    def removed(self, *args):
        for item in args:
            self.var.remove(item)

if __name__ == '__main__':
    x=Model('paulasda')