func (c *Command) GenZshCompletionFile(filename string) error {
	outFile, err := os.Create(filename)
	if err != nil {
		return err
	}
	defer outFile.Close()
	return c.GenZshCompletion(outFile)
}
GenZshCompletionFile generates zsh completion file.
package cobra
import (
	"bytes"
	"fmt"
	"io"
	"os"
	"strings"
)