Because Notes.app blew up on me, and here is the solution. :)

retrieve_notes.py

#!/usr/bin/env python
#
# Simple script to extract your notes from Notes.app's sqlite3 database. It
# places the HTML files in the current working directory. The database store
# should be located at:
#
# ~/Library/Containers/com.apple.Notes/Data/Library/Notes/NotesV1.storedata
#
# This file is released in the public domain.

import itertools
import re
import sqlite3
import sys

try:
    from html.parser import HTMLParser
except ImportError:
    from HTMLParser import HTMLParser


class NotesHTMLParser(HTMLParser):

    def __init__(self):
        HTMLParser.__init__(self)
        self.expecting_title = False
        self.note_title = None

    def handle_starttag(self, tag, attrs):
        if tag == 'body' and self.note_title is None:
            self.expecting_title = True

    def handle_data(self, data):
        if self.expecting_title:
            self.note_title = data
            self.expecting_title = False


def retrieve_notes_from_db(notes_file):
    with sqlite3.connect(notes_file) as conn:
        c = conn.cursor()
        c.execute('SELECT zhtmlstring FROM znotebody;')
        notes = c.fetchall()
        notes = list(itertools.chain(*notes))
        return filter(None, notes)


def create_note_html(note):
    parser = NotesHTMLParser()
    parser.feed(note)
    title = parser.note_title

    if not '</title>' in note:
        p = note.partition('</head>')
        assert p[1]
        note = p[0] + '<title></title>' + p[1] + p[2]

    p = note.partition('</title>')

    note = p[0] + title + p[1] + p[2]
        
    return (title, note)


if __name__ == '__main__':
    for arg in sys.argv[1:]:
        for note in retrieve_notes_from_db(arg):
            note = create_note_html(note)

            file_name = 'Note_' + re.sub('[^A-Za-z0-9 _-]+', '', note[0]) + '.html'
            with open(file_name, 'wb') as f:
                f.write(note[1].encode('utf-8'))
            sys.stderr.write('Wrote {0}\n'.format(file_name))