'Make a check_authentication request to verify this message.
@returns: True if the request is valid.
@rtype: bool'

def _checkAuth(self, message, server_url):

    oidutil.log('Using    OpenID    check_authentication')
    request = self._createCheckAuthRequest(message)
    if (request is None):
        return False
    try:
        response = self._makeKVPost(request, server_url)
    except (fetchers.HTTPFetchingError, ServerError) as e:
        oidutil.log(('check_authentication    failed:    %s' % (e[0],)))
        return False
    else:
        return self._processCheckAuthResponse(response, server_url)
