class Reveal(object):
    def __repr__(self):
        return "<%s %s>" % (self.__class__.__name__, self.__dict__)

class Yin(Reveal):
    def __init__(self, yin=100):
        self.yin = yin
        self.lightness = True
        self.darkness = False
        self.balance = False


class Yan(Reveal):
    def __init__(self, yan=100):
        self.yan = yan
        self.lightness = False
        self.darkness = True
        self.balance = False

class YinYan(Yin, Yan):
    def __init__(self, yin, yan):
        Yin.__init__(self, yin)
        Yan.__init__(self, yan)
        self.balance = True


yin = Yin(50)
yan = Yan(50)
yinyan = YinYan(50, 50)

print yin
print yan
print yinyan

# Prints
<Yin {'balance': False, 'yin': 50, 'lightness': True, 'darkness': False}>
<Yan {'balance': False, 'yan': 50, 'lightness': False, 'darkness': True}>
<YinYan {'balance': True, 'yin': 50, 'lightness': False, 'darkness': True, 'yan': 50}>

"""
    Send an email programmatically through Gmail.

    REFERENCES
    http://snippets.dzone.com/posts/show/757
    http://www.nixtutor.com/linux/send-mail-through-gmail-with-python/
    http://stackoverflow.com/questions/399129/#comment8985407_399240
"""
import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email.MIMEText import MIMEText
from email.Utils import COMMASPACE, formatdate
from email import Encoders
import os
from os.path import abspath, dirname, join

SMTP_SERVER = 'smtp.gmail.com:587'
SMTP_USER   = 'USER@gmail.com'
SMTP_PASS   = 'PASS'
EMAIL_FROM  = 'USER <%s>' % (SMTP_USER)

def send_gmail(to, subject, text, files=[]):
    assert type(to) == list
    assert type(files) == list
    from_ = EMAIL_FROM

    msg = MIMEMultipart()
    msg['From'] = EMAIL_FROM
    msg['To'] = COMMASPACE.join(to)
    msg['Date'] = formatdate(localtime=True)
    msg['Subject'] = subject

    msg.attach( MIMEText(text) )

    for file in files:
        part = MIMEBase('application', "octet-stream")
        part.set_payload( open(file,"rb").read() )
        Encoders.encode_base64(part)
        part.add_header('Content-Disposition', 'attachment; filename="%s"'
                       % os.path.basename(file))
        msg.attach(part)

    smtp = smtplib.SMTP(SMTP_SERVER)
    #smtp.set_debuglevel(1)
    smtp.ehlo()    # apparently this is required in python 2.5
    smtp.starttls()
    smtp.login(SMTP_USER, SMTP_PASS)
    smtp.sendmail(from_, to, msg.as_string() )
    smtp.close()


def test_email():
    to = 'YOUR_RECEPIENT@some_domain.com'
    subject = "Python Gmail Test"
    text = 'This is simply a test.'
    send_gmail([to], subject, text)
    print 'simple test complete'

def check_some_flag(method):
    def wrapper(self, *args, **kwargs):
        if not self.some_flag:
            raise Exception("some_flag not set")
        else:
            result = method(self, *args, **kwargs)
            return result
    return wrapper

>>> import numpy
>>> x = [1,50,99]
>>> y = [2,1,0.5]
>>> a,b,c = numpy.polyfit(x,y,2)
>>> f = lambda x: a*x**2 + b*x + c
>>> f(1)
2.0
>>> f(20)
1.5528946272386506
>>> f(50)
1.0000000000000002
>>> f(90)
0.55435235318617249
>>> f(100)
0.49500208246563937
>>> f(99)
0.5

diff -r c8f8537f5e21 -r 4e091af5eacf php/wikka/wikka.php
--- a/php/wikka/wikka.php	Tue Jan 17 10:01:24 2012 -0800
+++ b/php/wikka/wikka.php	Tue Jan 17 11:43:38 2012 -0800
@@ -509,11 +509,15 @@
 
 /**
  * Compare versions, start installer if necessary.
+ * Wait to start installer below if this is an upgrade so we can limit access
+ * to admin users.
  */
-if (!isset($wakkaConfig['wakka_version'])) $wakkaConfig['wakka_version'] = 0;
-if ($wakkaConfig['wakka_version'] !== WAKKA_VERSION)
-{
-	/**
+$is_new_install = ! isset($wakkaConfig['wakka_version']);
+$is_upgrade = $wakkaConfig['wakka_version'] !== WAKKA_VERSION;
+
+if ( $is_new_install ) {
+    $wakkaConfig['wakka_version'] = 0;
+    /**
 	 * Start installer.
 	 *
 	 * Data entered by the user is submitted in $_POST, next action for the
@@ -590,6 +594,7 @@
 	exit;
 }
 
+
 /**
  * Save session ID
  */
@@ -611,6 +616,39 @@
 }
 
 /**
+ * Check for upgrade. If so an user is admin, show setup page, else show
+ * a maintenance message to all other visitors.
+ */
+$is_admin = $wakka->IsAdmin($user);
+$at_install_step = ($_GET['installAction'] == 'writeconfig') && (isset($_POST['config']));
+$upgrade_allowed = $is_admin || $at_install_step;
+
+if ( $is_upgrade && $upgrade_allowed ) {
+	$installAction = 'default';
+	if (isset($_GET['installAction'])) $installAction = trim($_GET['installAction']);	#312
+	if (file_exists('setup'.DIRECTORY_SEPARATOR.'header.php'))
+	include('setup'.DIRECTORY_SEPARATOR.'header.php'); else print '<em class="error">'.ERROR_SETUP_HEADER_MISSING.'</em>'; #89
+	if
+	(file_exists('setup'.DIRECTORY_SEPARATOR.$installAction.'.php'))
+	include('setup'.DIRECTORY_SEPARATOR.$installAction.'.php'); else print '<em class="error">'.ERROR_SETUP_FILE_MISSING.'</em>'; #89
+	if (file_exists('setup'.DIRECTORY_SEPARATOR.'footer.php'))
+	include('setup'.DIRECTORY_SEPARATOR.'footer.php'); else print '<em class="error">'.ERROR_SETUP_FOOTER_MISSING.'</em>'; #89
+	exit;
+}
+elseif ( $is_upgrade && $_GET['install_help'] ) {
+    print "<h2> POST,GET, SESSION variables</h2>";
+    print '<pre>';
+    var_dump($_POST);
+    var_dump($_GET);
+    var_dump($_SESSION);
+    print '</pre>';
+}
+elseif ( $is_upgrade ) {
+    die('<h2>Site Undergoing Temporary Maintenance</h2><h4>Please check back shortly.</h4>');
+}
+
+
+/**
  * Run the engine.
  */
 if (!isset($handler)) $handler='';