hehe, okay, bad on me, I should have read the WHOLE module before commenting here.  I don't think you need these <code>'sysfs_sub_path', 'key2filename_dict', 'key2value_dict'</code> as properties w/ accessor methods (since you only define <code>get_()</code> anyway).  I think you can just use <code>@staticmethod</code>'s for them, see my comment below for explanation why:  https://github.com/cevich/virt-test/pull/8/files#r4022882