def METHOD_NAME(self):
    if self.selfconjugate:
        raise Exception('%s has no anti particle.' % self.name) 
    outdic = {}
    for k,v in self.__dict__.items():
        if k not in self.require_args_all:                
            outdic[k] = -v
    if self.color in [1,8]:
        newcolor = self.color
    else:
        newcolor = -self.color
    return Particle(-self.pdg_code, self.antiname, self.name, self.spin, newcolor, self.mass, self.width,
                    self.antitexname, self.texname, -self.charge, self.line, self.propagating, self.goldstoneboson, **outdic)