How to use the pyzotero.zotero_errors.UserNotAuthorised function in pyzotero

pass

        self.zot = None
        self.zotLastMod = None
        try:
            self.zot = zotero.Zotero(library_id, library_type, api_key)
            self.zotLastMod = self.zot.last_modified_version()  # v1.1.1

            DBInstance.dbInstanceCache[(library_id, library_type, api_key)] = self

            if library_type == 'group':
                log("Loading: https://www.zotero.org/groups/%s/items" % library_id)
            else:
                log("Loading: %s" % library_id)

        except zotero_errors.UserNotAuthorised:
            error("UserNotAuthorised: Set correct Zotero API key in settings.py for library ID %s." % library_id)
            raise SystemExit(1)

        return self

def error_handler(zot, req):
    """ Error handler for HTTP requests
    """
    error_codes = {
        400: ze.UnsupportedParams,
        401: ze.UserNotAuthorised,
        403: ze.UserNotAuthorised,
        404: ze.ResourceNotFound,
        409: ze.Conflict,
        412: ze.PreConditionFailed,
        413: ze.RequestEntityTooLarge,
        428: ze.PreConditionRequired,
        429: ze.TooManyRequests,
    }

    def err_msg(req):
        """ Return a nicely-formatted error message
        """
        return "\nCode: %s\nURL: %s\nMethod: %s\nResponse: %s" % (
            req.status_code,
            # error.msg,
            req.url,
            req.request.method,

def error_handler(req):
    """ Error handler for HTTP requests
    """
    error_codes = {
        400: ze.UnsupportedParams,
        401: ze.UserNotAuthorised,
        403: ze.UserNotAuthorised,
        404: ze.ResourceNotFound,
        409: ze.Conflict,
        412: ze.PreConditionFailed,
        413: ze.RequestEntityTooLarge,
        428: ze.PreConditionRequired,
        429: ze.TooManyRequests,
    }

    def err_msg(req):
        """ Return a nicely-formatted error message
        """
        return "\nCode: %s\nURL: %s\nMethod: %s\nResponse: %s" % (
            req.status_code,
            # error.msg,
            req.url,

def _verify_client_validity(self):
        # Check if Zotero can be accessed with current credentials
        try:
            self._client.collections()
        except zotero_errors.PyZoteroError as err:
            self._client = None
            if isinstance(err, zotero_errors.UserNotAuthorised):
                raise HTTPError(403)
            else:
                raise err

def _verify_client_validity(self):
        # Check if Zotero can be accessed with current credentials
        try:
            self._client.collections()
        except zotero_errors.PyZoteroError as err:
            self._client = None
            if isinstance(err, zotero_errors.UserNotAuthorised):
                raise HTTPError(403)
            else:
                raise err