1# Copyright (C) 2002-2006 Python Software Foundation 
    2# Author: Barry Warsaw 
    3# Contact: email-sig@python.org 
    4 
    5"""Base class for MIME type messages that are not multipart.""" 
    6from __future__ import unicode_literals 
    7from __future__ import division 
    8from __future__ import absolute_import 
    9 
    10__all__ = ['MIMENonMultipart'] 
    11 
    12from future.backports.email import errors 
    13from future.backports.email.mime.base import MIMEBase 
    14 
    15 
    16class MIMENonMultipart(MIMEBase): 
    17    """Base class for MIME multipart/* type messages.""" 
    18 
    19    def attach(self, payload): 
    20        # The public API prohibits attaching multiple subparts to MIMEBase 
    21        # derived subtypes since none of them are, by definition, of content 
    22        # type multipart/* 
    23        raise errors.MultipartConversionError( 
    24            'Cannot attach additional subparts to non-multipart/*')