zlib.so and libz.so and Python

[DeepBleu]

Python comes with zlib.so (for Sun OS).  But I noticed that on the same
machine, there is also libz.so
Can someone please tell me what is the difference between these two and what
libz.so is used for?  I am trying to troubleshoot a little problem and I
need to be certain that libz.so may or may not be used to work with ZIP
files along with Python.  Also, I want to find out if zlib.so (the one that
comes with the Python distribution) is all we need to work with ZIP files in
Python.
Thanks,
DeepBleu