As BlackJack said, you have an email with an attachment, which is mime encoded.
Basically when you send an email with an attachment, it gets encoded to plain text and then put into the body of the email. When you read an email, your email client reads the message, recognizes that there are encoded attachments and then decodes them and displays them as "attachments" which you can then save and use as whatever they were originally, .doc, .jpg, etc.
You will need to use Python to do the same thing. It will have to recognize that there are attachments and decode them and save them out to the file system.
Luckily the email library in python seems set up to do this, it will scan the whole message, figure out how many attachments there are (how many "parts", each attachment is a part) and then let you loop over the parts to decode and save them.
But if all you want is the body of the email messages, you can skip the part where it loops and decodes the attachments.
Here are a couple of examples of using python to decode multi part email messages, I haven't looked at them in detail to see what you would need to not do if you did not want the attachments decoded, but I bet you can figure it out.
http://code.activestate.com/recipes/866 ... ack-a-mul/