devstack stalls running setup.py install for python-mimeparse

Multiple failures this morning with devstack apparently failling after:

2013-10-10 09:15:10 Running setup.py develop for tempest
2013-10-10 09:15:10 Checking .pth file support in /usr/local/lib/python2.7/dist-packages/
2013-10-10 09:15:10 /usr/bin/python -E -c pass
2013-10-10 09:15:10 TEST PASSED: /usr/local/lib/python2.7/dist-packages/ appears to support .pth files
2013-10-10 09:15:10 [pbr] Reusing existing SOURCES.txt
2013-10-10 09:15:10 Creating /usr/local/lib/python2.7/dist-packages/tempest.egg-link (link to .)
2013-10-10 09:15:10 Adding tempest 2013.2.a1950.gb3e9c22 to easy-install.pth file
2013-10-10 09:15:10
2013-10-10 09:15:10 Installed /opt/stack/new/tempest
2013-10-10 09:15:10 Running setup.py install for extras
2013-10-10 09:15:10
2013-10-10 09:15:10 Running setup.py install for python-mimeparse

In successful runs it goes on to "Running setup.py install for python-subunit"...