Returns the plugins registered for the exporter.  If the optional
        flags are set then only plugins with the inputed flags will be
        returned.
        
        :param      flags | <XExporter.Flags>

def plugins(flags=None):
        """
        Returns the plugins registered for the exporter.  If the optional
        flags are set then only plugins with the inputed flags will be
        returned.
        
        :param      flags | <XExporter.Flags>
        """
        XExporter.init()
        
        plugs = XExporter._plugins[:]
        if flags is not None:
            return filter(lambda x: x.testFlag(flags), plugs)
        return plugs