Pythonでヤフーメールを受信

import os
import sys
import ssl
import imaplib
import email
from email.header import decode_header, make_header

def getSakubunLoginURL():
    ret = ""    #戻り値(ログインURL)
    server = 'imap.mail.yahoo.co.jp'    #yahooメール。

    # メールアドレスとログインパスワード
    usr = 'xxxx@yahoo.co.jp'
    password = 'xxxxx'

    try:
        context = ssl.create_default_context()
        imapclient = imaplib.IMAP4_SSL(server, 993, ssl_context=context)
        imapclient.login(usr,password)
        imapclient.select()
        typ, data = imapclient.search(None, 'all')

        data2 = data[0].split()
        num = data2[len(data2)-1]   #最新のやつだけ抽出
        typ, data = imapclient.fetch(num, '(RFC822)')
        email_message = email.message_from_bytes(data[0][1])
        email_from = str(make_header(decode_header(email_message['From'])))
        subject = str(make_header(decode_header(email_message['Subject'])))
        
    #        msg_encoding = 'iso-2022-jp'
        msg_encoding = 'utf-8'

        if email_message.is_multipart() == False: # シングルパート
            byt  = bytearray(email_message.get_payload(), msg_encoding)
            body = byt.decode(encoding=msg_encoding)
        else:   # マルチパート
            prt  = email_message.get_payload()[0]
            byt  = prt.get_payload(decode=True)
            body = byt.decode(encoding=msg_encoding)
        print('from:', email_from,'  subject:',subject)
        print('------------------------------------------')
        print(body)
        ret = body[body.find("https"):] #本文からURL抽出
        imapclient.close()
        imapclient.logout()
    except Exception as ee:
        sys.stderr.write("*** error ***\n")
        sys.stderr.write(str(ee) + '\n')
    
    return ret

getSakubunLoginURL()​