The example code has an example of how to attach files to notes:
# To include an attachment such as an image in a note, first create a Resource
# for the attachment. At a minimum, the Resource contains the binary attachment
# data, an MD5 hash of the binary data, and the attachment MIME type.
# It can also include attributes such as filename and location.
image = open('enlogo.png', 'rb').read()
md5 = hashlib.md5()
md5.update(image)
hash = md5.digest()
data = Types.Data()
data.size = len(image)
data.bodyHash = hash
data.body = image
resource = Types.Resource()
resource.mime = 'image/png'
resource.data = data
# Now, add the new Resource to the note's list of resources
note.resources = [resource]
# To display the Resource as part of the note's content, include an <en-media>
# tag in the note's ENML content. The en-media tag identifies the corresponding
# Resource using the MD5 hash.
hash_hex = binascii.hexlify(hash)
# The content of an Evernote note is represented using Evernote Markup Language
# (ENML). The full ENML specification can be found in the Evernote API Overview
# at http://dev.evernote.com/documentation/cloud/chapters/ENML.php
note.content = '<?xml version="1.0" encoding="UTF-8"?>'
note.content += '<!DOCTYPE en-note SYSTEM ' \
'"http://xml.evernote.com/pub/enml2.dtd">'
note.content += '<en-note>Here is the Evernote logo:<br/>'
note.content += '<en-media type="image/png" hash="' + hash_hex + '"/>'
note.content += '</en-note>'
The example code has an example of how to attach files to notes: