ImportError: cannot import name Encoders

[Mark Carter]

I'm using:
Python 2.2.1 (#34, Apr  9 2002, 19:34:33) [MSC 32 bit (Intel)] on win32

I tried the email example in section 12.2.10, which begins:

import smtplib

# Here are the email pacakge modules we'll need
from email import Encoders
from email.MIMEText import MIMEText

... etc.

but I get the error message:
ImportError: cannot import name Encoders

Is this a bug?
If not, then what's going on?

Thanks in advance.