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: carapace.go
    path of file: ./repos/sliver/vendor/github.com/rsteube/carapace
    
    the code of the file until where you have to start completion: // Package carapace is a command argument completion generator for spf13/cobra
package carapace

import (
	"os"

	"github.com/rsteube/carapace/internal/shell"
	"github.com/spf13/cobra"
	"github.com/spf13/pflag"
)

// Carapace wraps cobra.Command to define completions.

    
func (c Carapace) PreRun(f func(cmd *cobra.Command, args []string)) {
	if entry := storage.get(c.cmd); entry.prerun != nil {
		_f := entry.prerun
		entry.prerun = func(cmd *cobra.Command, args []string) {
			// TODO yuck - probably best to append to a slice in storage
			_f(cmd, args)
			f(cmd, args)
		}
	} else {
		entry.prerun = f
	}
}