编译时出现 no module named building

[jiyeyuran]

D:\iot\IoT_Camera\firmware>scons -j4
scons: Reading SConscript files ...
ImportError: No module named building:
  File "D:\iot\IoT_Camera\firmware\SConstruct", line 11:
    from building import *

[SummerGift]

查看一下有没有把rt-thread复制到firmware目录下？
这种提示一般是说找不到rt-thread源代码。