Scrapy使用MailSender发送邮件

# 邮箱配置
MAIL_HOST = "smtp.163.com"
MAIL_FROM = "xxx@163.com"
MAIL_USER = "xxx@163.com"
MAIL_PASS = "xxx"   # 授权码
MAIL_PORT = 25

# -*- coding: utf-8 -*-
import scrapy
from scrapy import cmdline
from scrapy.mail import MailSender
class SendEmailSpider(scrapy.Spider):
    name = 'send_email'
    start_urls = ['https://www.baidu.com/']
    def parse(self, response):
  # 方式一：读取配置文件中的配置
  # debug参数为True 不会发送邮件，仅仅打印日志
        mailer = MailSender(
            smtphost=self.settings["MAIL_HOST"],
            mailfrom=self.settings["MAIL_FROM"],
            smtpuser=self.settings["MAIL_USER"],
            smtppass=self.settings["MAIL_PASS"],
            smtpport=self.settings["MAIL_PORT"]
        )
        # 方式二：直接传入settings 对象
        mailer = MailSender.from_settings(self.settings)
  # 发送邮件
        return mailer.send(
            to=["xxx@qq.com"],
            subject="这是邮件标题",
            body="这是邮件内容"
        )
if __name__ == '__main__':
    cmdline.execute("scrapy crawl send_email".split())

mailer.send(
    to=["xxx@qq.com"],
    subject="这是邮件标题",
    body="这是邮件内容"
)

builtins.AttributeError: 'NoneType' object has no attribute 'bio_read'

mailer = MailSender()

Unable to send mail: To=['xxx@qq.com'] Cc=[] Subject="这是邮件标题" Attachs=0- 
Connection was refused by other side: 61: Connection refused.

class MailSender(object):
    def __init__(self, smtphost='localhost', mailfrom='scrapy@localhost',
            smtpuser=None, smtppass=None, smtpport=25, 
            smtptls=False, smtpssl=False, debug=False):
        self.smtphost = smtphost
        self.smtpport = smtpport
        self.smtpuser = _to_bytes_or_none(smtpuser)
        self.smtppass = _to_bytes_or_none(smtppass)
        self.smtptls = smtptls
        self.smtpssl = smtpssl
        self.mailfrom = mailfrom
        self.debug = debug

mailer = MailSender.from_settings(settings)

NameError: name 'settings' is not defined

import settings、
mailer = MailSender.from_settings(settings)

TypeError: 'module' object is not subscriptable

settings (scrapy.settings.Settings object)