You could/should use the email.parser
module to decode mail messages, for example (quick and dirty example!):
from email.parser import FeedParser
f = FeedParser()
f.feed("<insert mail message here, including all headers>")
rootMessage = f.close()
# Now you can access the message and its submessages (if it's multipart)
print rootMessage.is_multipart()
# Or check for errors
print rootMessage.defects
# If it's a multipart message, you can get the first submessage and then its payload
# (i.e. content) like so:
rootMessage.get_payload(0).get_payload(decode=True)
Using the “decode” parameter of Message.get_payload
, the module automatically decodes the content, depending on its encoding (e.g. quoted printables as in your question).