class Command(object):
    def __init__(self, type, value, target=None):
        self.type = type
        self.value = value
        if target is None:
            target = ''
        self.target = target
        self.sent = False

    def more(self):
        if self.sent:
            return ''
        self.sent = True
        ret = '%s:%s:%s\r\n' % (self.target, self.type, self.value)
        return ret

    def clone(self):
        return Command(self.type, self.value, self.target)