I am still using Debian 6. I installed python 2.7.8 but I am having problems to compile the seL4.

arduino@squeeze64:~/ARM/src/seL4$ TOOLPREFIX=arm-none-eabi- ARCH=arm PLAT=am335x ARMV=armv7-a CPU=cortex-a8 make
Traceback (most recent call last):
  File "./tools/invocation_header_gen.py", line 18, in <module>
    import tempita
ImportError: No module named tempita
make: *** [arch/api/invocation.h] Error 1

What is this module "tempita"? What package is that?