First, this is a customer-to-customer forum. Feel free to contact DH support via Contact Forum.
Hope this article will give you some thoughts. url]http://wiki.dreamhost.com/Python[/url]
Yes. You can enable web security in DH panel. If it is enabled, only you can see your directories thought you are on a shared server.
Probably not, you are still a limited user on PS. If the installation requires root priviledge, then it is not possible. However, you can install your own version of PHP, Python, etc.
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