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: wx_ServiceApi.go
    path of file: ./repos/gopay/examples/wechat
    
    the code of the file until where you have to start completion: package wechat

import (
	"net/http"

	"github.com/go-pay/gopay"
	"github.com/go-pay/gopay/wechat"
	"github.com/go-pay/util"
	"github.com/go-pay/xlog"
)

func GetAppWeChatLoginAccessToken() {
	accessToken, err := wechat.GetOauth2AccessToken(ctx, "AppID", "AppSecret", "code")
	if err != nil {
		xlog.Error("err:", err)
		return
	}
	xlog.Debug("AccessToken:", accessToke
    
func GetOpenIdByAuthCode() {
	// 授权码查询openid
	//    appId:APPID
	//    mchId:商户号
	//    apiKey:ApiKey
	//    authCode:用户授权码
	//    nonceStr:随即字符串
	openIdRsp, err := wechat.GetOpenIdByAuthCode(ctx, "wxdaa2ab9ef87b5497", "1368139502", "GFDS8j98rewnmgl45wHTt980jg543abc", "135127679952609396", util.RandomString(32))
	if err != nil {
		xlog.Error("err:", err)
		return
	}
	xlog.Debug("ReturnCode:", openIdRsp.ReturnCode)
	xlog.Debug("ReturnMsg:", openIdRsp.ReturnMsg)
	xlog.Debug("ResultCode:", openIdRsp.ResultCode)
	xlog.Debug("Appid:", openIdRsp.Appid)
	xlog.Debug("MchId:", openIdRsp.MchId)
	xlog.Debug("NonceStr:", openIdRsp.NonceStr)
	xlog.Debug("err_code:", openIdRsp.ErrCode)
	xlog.Debug("Openid:", openIdRsp.Openid)
}