'Connect to vCenter server and fetch version.
Can be over-ridden by setting \'vmware_host_version\' config.
:returns: vCenter version as a LooseVersion object'

def _get_vc_version(self):

    version_str = self.configuration.vmware_host_version
    if version_str:
        LOG.info('Using    overridden    vmware_host_version    from    config:    %s', version_str)
    else:
        version_str = vim_util.get_vc_version(self.session)
        LOG.info('Fetched    vCenter    server    version:    %s', version_str)
    return version_str
