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: mail.go
    path of file: ./repos/go-gin-api/pkg/mail
    
    the code of the file until where you have to start completion: package mail

import (
	"strings"

	"gopkg.in/gomail.v2"
)

type Options struct {
	MailHost string
	MailPort int
	MailUser string // 发件人
	MailPass string // 发件人密码
	MailTo   string // 收件人 多个用,分割
	Subject  string // 邮件主题
	Body     string 
    
func Send(o *Options) error {

	m := gomail.NewMessage()

	//设置发件人
	m.SetHeader("From", o.MailUser)

	//设置发送给多个用户
	mailArrTo := strings.Split(o.MailTo, ",")
	m.SetHeader("To", mailArrTo...)

	//设置邮件主题
	m.SetHeader("Subject", o.Subject)

	//设置邮件正文
	m.SetBody("text/html", o.Body)

	d := gomail.NewDialer(o.MailHost, o.MailPort, o.MailUser, o.MailPass)

	return d.DialAndSend(m)
}