How to use the pylxd.exceptions.ClientConnectionFailed function in pylxd

self.ssl_key = extra_parms["ssl_key"]
            self.ssl_cert = extra_parms["ssl_cert"]

            for _endpoint in access.split(',') :
                _endpoint_name, _endpoint_ip = hostname2ip(_endpoint.split('//')[1].split(':')[0], True)

                if _endpoint_ip not in self.lxdconn :
                    self.lxdconn[_endpoint_ip] = Client(endpoint = _endpoint, cert = (self.ssl_cert, self.ssl_key), verify = False)
                    self.lxdconn[_endpoint_ip].authenticate(credentials)
                    if not self.lxdconn[_endpoint_ip].trusted :
                        _fmsg = "Unable to authenticate"
                        _status = 101

            _status -= 100
            
        except LXDError.ClientConnectionFailed, obj:
            _status = 18127
            _fmsg = str(obj.message)

        except LXDError.LXDAPIException, obj:
            _status = 18127
            _fmsg = str(obj)
            
        except Exception, e :
            _status = 23
            _fmsg = str(e)

        finally :
            if _status :
                _msg = self.get_description() + " connection to endpoint \"" + _endpoint_ip + "\" failed: " + _fmsg
                cberr(_msg)                    
                raise CldOpsException(_msg, _status)

key
                        )
                    )

                log.debug((
                    'Trying to connecto to "{0}" '
                    'with cert "{1}", key "{2}" and '
                    'verify_cert "{3!s}"'.format(
                        remote_addr, cert, key, verify_cert)
                ))
                client = pylxd.Client(
                    endpoint=remote_addr,
                    cert=(cert, key,),
                    verify=verify_cert
                )
    except pylxd.exceptions.ClientConnectionFailed:
        raise CommandExecutionError(
            "Failed to connect to '{0}'".format(remote_addr)
        )

    except TypeError as e:
        # Happens when the verification failed.
        raise CommandExecutionError(
            ('Failed to connect to "{0}",'
             ' looks like the SSL verification failed, error was: {1}'
             ).format(remote_addr, six.text_type(e))
        )

    _connection_pool[pool_key] = client

    return client

else:
                path = '/var/lib/lxd/unix.socket'
            endpoint = 'http+unix://{}'.format(parse.quote(path, safe=''))
            self.api = _APINode(endpoint, timeout=timeout)
        self.api = self.api[version]

        # Verify the connection is valid.
        try:
            response = self.api.get()
            if response.status_code != 200:
                raise exceptions.ClientConnectionFailed()
            self.host_info = response.json()['metadata']

        except (requests.exceptions.ConnectionError,
                requests.exceptions.InvalidURL) as e:
            raise exceptions.ClientConnectionFailed(str(e))

        self.cluster = managers.ClusterManager(self)
        self.certificates = managers.CertificateManager(self)
        self.containers = managers.ContainerManager(self)
        self.images = managers.ImageManager(self)
        self.networks = managers.NetworkManager(self)
        self.operations = managers.OperationManager(self)
        self.profiles = managers.ProfileManager(self)
        self.storage_pools = managers.StoragePoolManager(self)

else:
            if 'LXD_DIR' in os.environ:
                path = os.path.join(os.environ.get('LXD_DIR'), 'unix.socket')
            elif os.path.exists('/var/snap/lxd/common/lxd/unix.socket'):
                path = '/var/snap/lxd/common/lxd/unix.socket'
            else:
                path = '/var/lib/lxd/unix.socket'
            endpoint = 'http+unix://{}'.format(parse.quote(path, safe=''))
            self.api = _APINode(endpoint, timeout=timeout)
        self.api = self.api[version]

        # Verify the connection is valid.
        try:
            response = self.api.get()
            if response.status_code != 200:
                raise exceptions.ClientConnectionFailed()
            self.host_info = response.json()['metadata']

        except (requests.exceptions.ConnectionError,
                requests.exceptions.InvalidURL) as e:
            raise exceptions.ClientConnectionFailed(str(e))

        self.cluster = managers.ClusterManager(self)
        self.certificates = managers.CertificateManager(self)
        self.containers = managers.ContainerManager(self)
        self.images = managers.ImageManager(self)
        self.networks = managers.NetworkManager(self)
        self.operations = managers.OperationManager(self)
        self.profiles = managers.ProfileManager(self)
        self.storage_pools = managers.StoragePoolManager(self)