Python MIME 图像被视为附件 - 不是信件正文的一部分

Question

我正在发送 email 消息，其中包含如下正文中的图像：

    message = MIMEMultipart("mixed")
    message['Subject'] = SUBJECT
    message['From'] = email.utils.formataddr((SENDERNAME, SENDER))
    message['To'] = RECIPIENT

    relatedBody = MIMEMultipart("related")

    messageBody = MIMEMultipart("alternative")

    part1 = MIMEText(BODY_TEXT, 'plain')
    part2 = MIMEText(BODY_HTML, 'html')

    messageBody.attach(part1)
    messageBody.attach(part2)

    relatedBody.attach(messageBody)

    if logo_image:
        logo_img = MIMEImage(logo_image, logo_format)
        logo_img.add_header('Content-Id', '<logo_image>')  # angle brackets are important
        logo_img.add_header("Content-Disposition", "inline", filename="myimage")
        relatedBody.attach(logo_img)

    if hero_image:
        hero_img = MIMEImage(hero_image, hero_format)
        hero_img.add_header('Content-Id', '<hero_image>')  # angle brackets are important
        hero_img.add_header("Content-Disposition", "inline", filename="myimage")
        relatedBody.attach(hero_img)

    message.attach(relatedBody)

然而，它们通常被视为信件中的附件，而不是正文中的图像。 有没有办法解决它？