conda升级anaconda　ValueError的解决办法

查到了这个：anaconda update issue

I have narrowed this down to the following packages:

package	build
psutil-1.2.1	py27_0 hard-link
pycparser-2.10	py27_0 hard-link
pykit-0.1.0	np18py27_2 hard-link
pyparsing-2.0.1	py27_0 hard-link

by calling “conda install anaconda” and then successfully installing everything else one at a time.
These four packages consistently exhibit the described behaviour.
(note: pykit depends on pycparser so may itself be ok – can’t tell)

我先把psutil卸载掉，重新update了一下，成功。