def METHOD_NAME(letter: models.Letter, pdf_bytes: bytes):
    if letter.letter_emailed_at is not None:
        logger.info(f"{letter} has already been emailed to the landlord.")
        return False
    ld = letter.user.landlord_details
    assert ld.email
    if is_not_demo_deployment(f"emailing {letter} to landlord"):
        letter_type = letter.get_letter_type()
        email_react_rendered_content_with_attachment(
            SITE_CHOICES.LALETTERBUILDER,
            letter.user,
            LALETTERBUILDER_EMAIL_TO_LANDLORD_URL,
            recipients=[ld.email],
            attachment=laletterbuilder_pdf_response(pdf_bytes, letter_type),
            # Force the locale of this email to English, since that's what the
            # landlord will read the email as.
            locale=locales.DEFAULT,
        )
    letter.letter_emailed_at = timezone.now()
    letter.save()
    return True