$ cheetah-compile categoryselection.tmpl categoryselection.py 
Compiling categoryselection.tmpl -> categoryselection.py (backup categoryselection.py.bak)
Compiling categoryselection.py -> categoryselection.py.py
Traceback (most recent call last):
  File "/usr/bin/cheetah-compile", line 5, in ?
    CheetahWrapper().main()
  File "/usr/lib/python2.4/site-packages/Cheetah/CheetahWrapper.py", line 183, in main
    meth()
  File "/usr/lib/python2.4/site-packages/Cheetah/CheetahWrapper.py", line 240, in compile
    self._compileOrFill()
  File "/usr/lib/python2.4/site-packages/Cheetah/CheetahWrapper.py", line 347, in _compileOrFill
    self._compileOrFillBundle(b)
  File "/usr/lib/python2.4/site-packages/Cheetah/CheetahWrapper.py", line 557, in _compileOrFillBundle
    raise Error("""\
Cheetah.CheetahWrapper.Error: categoryselection.py: base name categoryselection.py contains invalid characters.  It must
be named according to the same rules as Python modules.