buildout error on plone 5

Hello Everybody,

I am following these instructions for plone5:
http://docs.plone.org/manage/installing/requirements.html in order to
install plone5 for my own joy but I got the following error running
buildout.

p.d. The same machine is used for running plone4 and works ok.

(plone5.0)plone-demo@plone:/usr/local/plone5.0/zinstance$ ./bin/buildout
While:
  Installing.
  Checking for upgrades.
  Getting distribution for 'zc.buildout==2.4.3'.

An internal error occurred due to a bug in either zc.buildout or in a
recipe being used:
Traceback (most recent call last):
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/buildout.py",
line 1992, in main
    getattr(buildout, command)(args)
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/buildout.py",
line 515, in install
    self._maybe_upgrade()
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/buildout.py",
line 950, in _maybe_upgrade
    allow_hosts = self._allow_hosts
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/easy_install.py",
line 848, in install
    return installer.install(specs, working_set)
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/easy_install.py",
line 635, in install
    for_buildout_run=for_buildout_run):
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/easy_install.py",
line 477, in _get_dist
    dist, avail = self._satisfied(requirement)
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/easy_install.py",
line 234, in _satisfied
    return None, self._obtain(req, source)
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/easy_install.py",
line 420, in _obtain
    if _final_version(dist.parsed_version)
  File
"/usr/local/plone5.0/zinstance/eggs/zc.buildout-2.4.4-py2.7.egg/zc/buildout/easy_install.py",
line 1407, in _final_version
    return not parsed_version.is_prerelease
AttributeError: 'tuple' object has no attribute 'is_prerelease'


-- 
Typed on my key64.org keyboard

Nestor A Diaz


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