Description of problem:


Version-Release number of selected component (if applicable):
3.3x

Steps to Reproduce:
1. in a terminal, type
    calibre


2. calibre starts to run, but before showing any window, crashes.

    sys.exit(calibre())
  File "/usr/lib64/calibre/calibre/gui_launch.py", line 72, in calibre
    from calibre.gui2.main import main
  File "/usr/lib64/calibre/calibre/gui2/__init__.py", line 22, in <module>
    from calibre.utils.date import UNDEFINED_DATE
  File "/usr/lib64/calibre/calibre/utils/date.py", line 14, in <module>
    from calibre.utils.iso8601 import utc_tz, local_tz, UNDEFINED_DATE
  File "/usr/lib64/calibre/calibre/utils/iso8601.py", line 8, in <module>
    from dateutil.tz import tzlocal, tzutc, tzoffset
  File "/usr/lib/python2.7/site-packages/dateutil/tz/__init__.py", line 2, in <module>
    from .tz import *
  File "/usr/lib/python2.7/site-packages/dateutil/tz/tz.py", line 19, in <module>
    from six.moves import _thread
ImportError: cannot import name _thread


This was reported on other distributions and fixed by updating calibre to 3.4 - e.g.
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=868379