google python3 api发送电子邮件示例

我在他们的网站上举了一个例子：

基本上，我想使用create_message_with_attachment（）和send_message（）来发送电子邮件。以下是我目前得到的信息：

#send our spreadsheet
from __future__ import print_function
import httplib2
import os

from apiclient import discovery
from apiclient import errors
from googleapiclient import http
from oauth2client import client
from oauth2client import tools
from oauth2client.file import Storage
from apiclient.http import MediaIoBaseDownload
import io

import mimetypes 
from email import encoders
from email.message import Message
from email.mime.audio import MIMEAudio
from email.mime.base import MIMEBase
from email.mime.image import MIMEImage
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
import base64

def create_message_with_attachment(
    sender, to, subject, message_text, file):
  """Create a message for an email.

  Args:
    sender: Email address of the sender.
    to: Email address of the receiver.
    subject: The subject of the email message.
    message_text: The text of the email message.
    file: The path to the file to be attached.

  Returns:
    An object containing a base64url encoded email object.
  """
  message = MIMEMultipart()
  message['to'] = to
  message['from'] = sender
  message['subject'] = subject

  msg = MIMEText(message_text)
  message.attach(msg)

  content_type, encoding = mimetypes.guess_type(file)

  if content_type is None or encoding is not None:
    content_type = 'application/octet-stream'
  main_type, sub_type = content_type.split('/', 1)
  fp = open(file, 'rb')
  msg = MIMEBase(main_type, sub_type)
  msg.set_payload(fp.read())
  fp.close()
  filename = os.path.basename(file)
  msg.add_header('Content-Disposition', 'attachment', filename=filename)
  message.attach(msg)

  return {'raw': base64.urlsafe_b64encode(message.as_string())}
  #return {'raw': base64.urlsafe_b64encode(message.as_bytes())}


def send_message(service, user_id, message):
  """Send an email message.

  Args:
    service: Authorized Gmail API service instance.
    user_id: User's email address. The special value "me"
    can be used to indicate the authenticated user.
    message: Message to be sent.

  Returns:
    Sent Message.
  """
  try:
    message = (service.users().messages().send(userId=user_id, body=message)
               .execute())
    print('Message Id: %s' % message['id'])
    return message
  except errors.HttpError as error:
    print('An error occurred: %s' % error)

def main(mail_service,spreadsheetId,new_invoice_filename):
    print('We are emailing the spreadsheet.')
    sender = 'me'
    to = 'me'
    subject = 'test '+new_filename
    message_text = 'Hi sdf \n P '
    attachment = 'D:/My Documents/file.pdf'
    msg = create_message_with_attachment(sender, to, subject, message_text, attachment)

    send_message(mail_service, sender, msg)

所以在文档中，它说create_message_with_attachment将专门返回raw字段，但是当我使用send_message（）发送消息时，我不知道如何将我得到的raw放入其中

所以我真的很困惑

谢谢