设$f\left(x\right)$是定义在R上的函数且$f\left(x\right)=\frac{1+f\left(x-2\right)}{1-f\left(x-2\right)}$，且$f\left(3\right)=2+\sqrt{3}$，则$f\left(2007\right)=（ \; ）$

阅读诗歌，完成后面小题。
                                                                                            谢亭送别
                                                                                                许浑
                                                                     劳歌一曲解行舟，红叶青山水急流。
                                                                     日暮酒醒人已远，满天风雨下西楼。
                                                                    【注】①劳歌：送别歌。