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: build.go
    path of file: ./repos/streamdal/apps/cli/vendor/github.com/alecthomas/kong
    
    the code of the file until where you have to start completion: package kong

import (
	"fmt"
	"reflect"
	"strings"
)

// Plugins are dynamically embedded command-line structures.
//
// Each element in the Plugins list *must* be a pointer to a structure.
type Plugins []interface{}

func build(k *Kong, ast interface{}) (app *Appl
    
func buildGroupForKey(k *Kong, key string) *Group {
	if key == "" {
		return nil
	}
	for _, group := range k.groups {
		if group.Key == key {
			return &group
		}
	}

	// No group provided with kong.ExplicitGroups. We create one ad-hoc for this key.
	return &Group{
		Key:   key,
		Title: key,
	}
}