I have no knowledge of Python. I started with .NET and than learned PHP. Someone later asked me to learn Ruby as well. I started learning it. Since last few months I am seeing many libraries and drivers written in Python. I want to know what are the advantages of Python over PHP/Ruby? What type of language it is and is there a need to learn Python as well?
Which is the purest version of Python? I could see many variants there like IronPython etc.
Nobody can tell you the exact answer because everybody has their own "holy grail". You will just have to find out for yourself which one suits you best for the task you want to perform. Case closed.
If you're just getting started in python, chances are the standard python distribution will work just fine. Once you get into the guts of your project, changing to IronPython (etc) is not a big deal.
I think the most important part is the "getting started" piece. Start writing python and you'll never look back.