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: completions.go
    path of file: ./repos/langchaingo/llms/local/internal/localclient
    
    the code of the file until where you have to start completion: package localclient

import (
	"context"
	"os/exec"
)

type completionPayload struct {
	Prompt string `json:"prompt"`
}

type completionResponsePayload struct {
	Response string
}

func (c *Client
    
func (c *Client) createCompletion(ctx context.Context, payload *completionPayload) (*completionResponsePayload, error) {
	// Append the prompt to the args
	c.Args = append(c.Args, payload.Prompt)

	// #nosec G204
	out, err := exec.CommandContext(ctx, c.BinPath, c.Args...).Output()
	if err != nil {
		return nil, err
	}

	return &completionResponsePayload{
		Response: string(out),
	}, nil
}