def METHOD_NAME(form, field):
    if email_safe(field.data) != field.data.lower():
        # fix their data instead of only warning them
        field.data = email_safe(field.data)
        raise ValidationError(_l("Make sure we formatted your email address correctly."))
    if len(field.data) > 64:
        raise ValidationError(_l("This cannot exceed 64 characters in length"))
    # this filler is used because service id is not available when validating a new service to be created
    service_id = getattr(form, "service_id", current_app.config["NOTIFY_BAD_FILLER_UUID"])
    unique_name = service_api_client.is_service_email_from_unique(service_id, field.data)
    if not unique_name:
        raise ValidationError(_l("This email address is already in use"))