'version of ghostscript.'

@property
def gs_version(self):

    try:
        return self._cached[u'gs_version']
    except KeyError:
        pass
    from matplotlib.compat.subprocess import Popen, PIPE
    s = Popen([self.gs_exe, u'--version'], stdout=PIPE)
    (pipe, stderr) = s.communicate()
    if six.PY3:
        ver = pipe.decode(u'ascii')
    else:
        ver = pipe
    try:
        gs_version = tuple(map(int, ver.strip().split(u'.')))
    except ValueError:
        gs_version = (0, 0)
    self._cached[u'gs_version'] = gs_version
    return gs_version
