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: completion_commmand.go
    path of file: ./repos/etcd/etcdutl/etcdutl
    
    the code of the file until where you have to start completion: // Copyright 2021 The etcd Authors
//
// 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 etcdutl

import (
	"os"

	"github.com/spf13/cobra"
)

func NewCompletionCommand() *cobra.Command {
	cmd := &cobra.Command{
		Use:   "completion [bash|zsh|fish|powershell]",
		Short: "Generate completion script",
		Long: `To load completions:

Bash:

  $ source <(etcd
    
func NewCompletionCommand() *cobra.Command {
	cmd := &cobra.Command{
		Use:   "completion [bash|zsh|fish|powershell]",
		Short: "Generate completion script",
		Long: `To load completions:

Bash:

  $ source <(etcdutl completion bash)

  # To load completions for each session, execute once:
  # Linux:
  $ etcdutl completion bash > /etc/bash_completion.d/etcdutl
  # macOS:
  $ etcdutl completion bash > /usr/local/etc/bash_completion.d/etcdutl

Zsh:

  # If shell completion is not already enabled in your environment,
  # you will need to enable it.  You can execute the following once:

  $ echo "autoload -U compinit; compinit" >> ~/.zshrc

  # To load completions for each session, execute once:
  $ etcdutl completion zsh > "${fpath[1]}/_etcdutl"

  # You will need to start a new shell for this setup to take effect.

fish:

  $ etcdutl completion fish | source

  # To load completions for each session, execute once:
  $ etcdutl completion fish > ~/.config/fish/completions/etcdutl.fish

PowerShell:

  PS> etcdutl completion powershell | Out-String | Invoke-Expression

  # To load completions for every new session, run:
  PS> etcdutl completion powershell > etcdutl.ps1
  # and source this file from your PowerShell profile.
`,
		DisableFlagsInUseLine: true,
		ValidArgs:             []string{"bash", "zsh", "fish", "powershell"},
		Args:                  cobra.ExactValidArgs(1),
		Run: func(cmd *cobra.Command, args []string) {
			switch args[0] {
			case "bash":
				cmd.Root().GenBashCompletion(os.Stdout)
			case "zsh":
				cmd.Root().GenZshCompletion(os.Stdout)
			case "fish":
				cmd.Root().GenFishCompletion(os.Stdout, true)
			case "powershell":
				cmd.Root().GenPowerShellCompletionWithDesc(os.Stdout)
			}
		},
	}

	return cmd
}