You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: boot_token.go
    path of file: ./repos/pipeline/pkg/k8sutil
    
    the code of the file until where you have to start completion: // Copyright Â© 2019 Banzai Cloud
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package k8sutil

import (
	"context"
	"time"

	"emperror.dev/errors"
	"github.com/sirupsen/logrus"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/kubernetes"
	"k8s.io/cluster-bootstrap/token/util"
	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
)

const (
	KubeSystemNamespace          = "kube-system"
	TokenSecretTypeFieldSelector = "type=bootstrap.kubernetes.io/token"
)

// GetOrCreateBootstrapToken
// This function will ensure to have at least 1 token that expire at least 1 hour from now
// GetOrCreateBootstrapToken returns a token for joining the cluster, creating a new one if there isn't any with enough time until expiration
func GetOrCreateBootstrapToken(ctx context.Context, log logrus.FieldLogger, client kubernetes.Interface) (string, error) {
	namespace := KubeSystemNamespace
	options := metav1.ListOptions{
		FieldSelector: TokenSec
    
func GetOrCreateBootstrapToken(ctx context.Context, log logrus.FieldLogger, client kubernetes.Interface) (string, error) {
	namespace := KubeSystemNamespace
	options := metav1.ListOptions{
		FieldSelector: TokenSecretTypeFieldSelector,
	}
	secrets, err := client.CoreV1().Secrets(namespace).List(ctx, options)
	if err != nil {
		return "", errors.WrapIfWithDetails(err, "namespace", namespace)
	}
	for _, s := range secrets.Items {
		token, err := kubeadm.BootstrapTokenFromSecret(&s)
		if err != nil {
			return "", errors.WrapIf(err, "unable to parse token")
		}
		log.Debugf("Token found %s with expiration %s", token.Token, token.Expires)
		// Check expiration for token to be at least 10Minute available
		expiration := metav1.NewTime(token.Expires.Add(time.Minute * 10))
		now := metav1.Now()
		if now.Before(&expiration) {
			return token.Token.String(), nil
		}
	}
	tokenValue, err := util.GenerateBootstrapToken()
	if err != nil {
		return "", errors.WrapIf(err, "bootstrap token generation failed")
	}
	tokenString, err := kubeadm.NewBootstrapTokenString(tokenValue)
	if err != nil {
		return "", errors.WrapIf(err, "bootstrap token generation failed")
	}
	token := kubeadm.BootstrapToken{
		Token:       tokenString,
		TTL:         &metav1.Duration{Duration: time.Hour * 1},
		Description: "Pipeline Node bootstrap token",
		Usages:      []string{"authentication", "signing"},
		Groups:      []string{"system:bootstrappers:kubeadm:default-node-token"},
	}
	_, err = client.CoreV1().Secrets(namespace).Create(ctx, token.ToSecret(), metav1.CreateOptions{})
	if err != nil {
		return "", errors.WrapIf(err, "unable to create token")
	}
	return tokenString.String(), nil
}