If anyone's still reading this in 2015, I came across the same issue, and didn't like any of the existing solutions. So, I brute forced it by writing some code to scrape the TOC of the Standard Library page in the official Python docs. I also built a simple API for getting a list of standard libraries (for Python version 2.6, 2.7, 3.2, 3.3, and 3.4).
The package is here, and its usage is fairly simple:
>>> from stdlib_list import stdlib_list
>>> libraries = stdlib_list("2.7")
>>> libraries[:10]
['AL', 'BaseHTTPServer', 'Bastion', 'CGIHTTPServer', 'ColorPicker', 'ConfigParser', 'Cookie', 'DEVICE', 'DocXMLRPCServer', 'EasyDialogs']
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