*mpl_toolkits.ps_cmyk* module provides a ps backend that saves images (and only images) in CMYK colorspace. It depends on *lcms* for color conversion, i.e., you need to have lcms and its python module installed (http://www.littlecms.com/). It contains sample of icc files but needs you also download icc files from Adobe. To install, download "AdobeICCProfilesCS4Mac_end-user.zip" from http://www.adobe.com/support/downloads/detail.jsp?ftpID=4074 and place it in the same directory as setup.py. Then run "python setup.py install".