Not installing on osx

I am using the comand line on osx to install zfn like the readme tells me to. And after running the comand python setup.py install i get the error:
Traceback (most recent call last):
  File "setup.py", line 27, in <module>
    from ez_setup import use_setuptools
ImportError: No module named ez_setup

My osx is at 10.5.4 running on 1 gig ram and a core 2 duo processor. And the source code i downloaded was 0.1 i tried both the gzip and bzip2 files to make sure it just wasn't a bad un-compression.